D&D 5E Psionics in Tasha

[glass]

My players where in a dark sewer and I told them there where rats scuttling about. If anyone had said "I look at the rats" I would have mentioned their exposed brains, but they chose not to give the rats a second glance.

Whereas I would say "you see a bunch of rats with exposed glowing brains", because that is a really obvious thing that the PCs would definitely notice but the players have no way of knowing unless I tell them. And if a GM tried to pull "you didn't say you looked at the rats specifically" with me I would be unimpressed to say the least.

_
glass.

 

[Maxperson]

WoTC is just as likely to release spells with components and call that Psionics as they are to release your vision of Psionics. But, since there is no official psionic class, then talking about hypothetical builds is all we can do.

That's not true. We can see from the MM monsters and all of the UAs dealing with psionics that WotC's vision of psionics is one that doesn't need components. They are far more likely to release my vision of psionics if they ever get around to releasing one.

You then swooped in to tell me that adding Displays to Psionics was completely uncontreversial and I should assume that Sabathius also supports displays for Psionics as does everyone else, and Paul is engaging in Strawmen. Which was not something he ever said, nor the actual topic of discussion.

He has now. He said he was fine with displays as a balance.

Also, you might notice I grouped all your responses together. You seemed to want to respond to my single overarching argument by breaking it into smaller pieces. This was fairly aggravating since, for example, you responded to me restating the premise by treating it like an argument.

Responding to "you can't counter a psionist by tying and gagging them" by telling me that PCs are very rarely bound and gagged doesn't really address the point. Especially since I had those two lines, not as arguments, but to show where we were standing in the discussion.

Most of this actually is you responding to a critique of your lack of detail, as though you gave me actual answers to discuss. I mean, the entire point of my paragraph was that you did not give me actual ways to balance the classes, yet in this response you say " Proposing ways to balance that has everything to do with the point." Sure Max, it would. But in that post I was responding to, you did not propose any ways to balance it. You instead said "you can quite easily balance the inability to stop them from casting through immobilization and silence, in other ways. It's not as if they can't be given slight disadvantages somewhere else to compensate."

Look, you may not like my ideas on how to balance them, but I did in fact give you ways to balance the class. Making the class abilities slightly weaker and/or reducing spell slots or the equivalent are ways to balance binding/gagging not working to stop psionic casting.

As for the actual point you made that I can address, no, I am not solely concerned with the balance in combat. Combat is actually the point I am the least concerned about, for a few reasons.

1) My players do not tend to be highly tactical. I have tried to get various groups to a higher level of tactical thinking, but they aren't interested

2) My players are concerned with "rule of cool" type moments. So, if the Psion wanted to throw an enemy with telekinesis, they are far more likely to describe it as them gritting their teeth and throwing out their hands than they are to be standing in cover and staring really hard. Meaning a lot of Somatic and Verbal indicators (note I did not say components) are likely to be included whether or not they are needed. Therefore identifying them in combat (on top of other things like enemies not exactly standing idly by as a guy who is standing around staring at people who are getting flung around the room is in the combat) Leading us to...

3) The issue of safe containment and transport of dangerous individuals is something we see fairly often in my games. Both when I am a player and when I am a DM. And we have struggled enough with simply securing wizards and other magic users, that this issue with Psionics immediately jumps out at me as being hard to navigate as a player, and challenging world building to a degree. Mundane methods can restrain even an Archmage. Current discussions have no way to fully restrain even the weakest Psion. Which means a dangerous Psion would be killed on the spot, because you have no way to contain them or restrain their power. This is a big deal.

I gave you ways to restrain them and their power twice now. It just takes a bit of thought.

The idea of devoting your watch to keeping a perfect eye on your prisoner runs into a few other problems. For example, how well are you actually keeping watch if you are staring at the prisoner?

It runs risks, sure. Depending on how many PCs are in the part. Some things in the game are a challenge.

Can you keep your sword to their throat while marching?

Yes.

If they have charm abilities, can you be sure that you can get your readied action off in time if they have a readied action to whammy you when you are distracted?

Also yes. That's what a readied action does. It interrupts when the trigger happens and you get to go first.

I would say it is very difficult to hold a readied action of a sword held against someone's throat, while keeping your full attention on that person for two hours. Possible, but incredibly difficult.

Trade off. Fighter does it, then rogue does it, and then bard does it. Then rest.

Also, if you can just kill them, why didn't you? Supposedly you are transporting them for a reason. If you could kill them with no repurcussions, you would have just done so.

There are literally thousands of reasons why you didn't kill them in combat, but would if they continued to attack you. Pick one.

Finally, you are wrong about NPCs having no hit dice. First of all, this NPC is a Psion, so they do have class levels. That's why they have psionic abilities. Secondly, every statblock has Hit Dice.

So first, no. Only rare(if any) NPCs have class levels. NPC casters just cast similar to PC classes. They don't actually possess class levels. Second, I'm talking about hit dice to regain hit points, not hit dice you roll for their original hit points. That should have been clear when I referenced rolling hit dice to heal.

So, if we assume the Psion has a similiar statblock to the mage, they would have 9d8 Hit dice, that they could spend after an hour rest to recover. They can only spend those nine, unless they get a long rest, but if they have enough to survive an exchange with the guard on Watch, they could potentially overwhelm the guard and escape.

Don't assume. Use RAW. There are no class levels involved in any NPC stat blocks in the MM. Monsters/NPCs and PCs do not use the same rules unless the DM chooses that option when creating the NPC. As you note in your hit point quote, RAW does not give monsters hit dice to heal with. It only gives them initial hit points.

I have seen a lot of people argue that the Psion should not even have to see you, to attack you. I would also argue that Clairvoyance shouldn't work for casting, but then that leads to the Psion not even having clairvoyant or "sight beyond sight" abilities. Which, are fairly iconic abilities for Psionics.

I could see the argument being made for Clairvoyance to work to see things that are beyond line of sight, but not work for powers to work through.

And I break posts apart like that because I have ADHD and if I don't start responding to portions as I encounter them, I will forget a lot of what I have to say. I'm sorry if it's annoying to you, but it's the way I have to respond.

 

[Chaosmancer]

Whereas I would say "you see a bunch of rats with exposed glowing brains", because that is a really obvious thing that the PCs would definitely notice but the players have no way of knowing unless I tell them. And if a GM tried to pull "you didn't say you looked at the rats specifically" with me I would be unimpressed to say the least.

_
glass.

They would notice if the rats glowed.

Of course, as I said previously, the Rats can choose whether or not they glow. Intelligence 15. If my players are smart enough to think "is holding a torch going to make me more obvious" the cranium rat is capable of thinking "is glowing going to make me more obvious" and turn off the lights.

And, again, poor light conditions, small creature, moving fast, they may seek a pink streak on the rat's head, but you may not actually be able to see the fact that it is an exposed brain. It is a perfectly reasonable detail that they may miss

 

[Maxperson]

They would notice if the rats glowed.

Of course, as I said previously, the Rats can choose whether or not they glow. Intelligence 15. If my players are smart enough to think "is holding a torch going to make me more obvious" the cranium rat is capable of thinking "is glowing going to make me more obvious" and turn off the lights.

And, again, poor light conditions, small creature, moving fast, they may seek a pink streak on the rat's head, but you may not actually be able to see the fact that it is an exposed brain. It is a perfectly reasonable detail that they may miss

Unless it's really dim light, there's virtually no way to miss exposed brains in a swarm of rats. Even in a single rat it would be pretty easy to notice.

 

[Chaosmancer]

That's not true. We can see from the MM monsters and all of the UAs dealing with psionics that WotC's vision of psionics is one that doesn't need components. They are far more likely to release my vision of psionics if they ever get around to releasing one.

You are welcome to that opinion, but it is based on no evidence, and countered by Tasha's releasing Psionic spells.

He has now. He said he was fine with displays as a balance.

"He has now" meaning you acknowledge he had not before.
Meaning you insisting that I should assume his answer, was still incorrect.

Also, he additionally said he was neutral on components. So he would be fine with components in Psionic powers (VSM to be specific of what I am talking about) so, the person whom you insisted completely agrees with your point of view, disagrees with your core and fundamental argument.

So, again, you jumping in and telling me what I should assume about his argument, was improper at best.

Look, you may not like my ideas on how to balance them, but I did in fact give you ways to balance the class. Making the class abilities slightly weaker and/or reducing spell slots or the equivalent are ways to balance binding/gagging not working to stop psionic casting.


I gave you ways to restrain them and their power twice now. It just takes a bit of thought.

1) I am allowed to not be convinced by your ways of balancing, especially since

2) Making the class abilities weaker does not solve the problem I put forth. In fact, it does not matter at all to the problem I put forth. Sort of like solving the problem of "I am worried my house will catch fire" by giving me car insurance. Yes, that is a good thing for me to have, but it sort of does nothing for the problem about the house.

It runs risks, sure. Depending on how many PCs are in the part. Some things in the game are a challenge.

Some things are a challenge. A completely empty statement that sort of just vaguely waves away the problem.

Yes.

Well, I'm glad that you can hold a 3 lb length of steel to someone's neck while on an 8 hour march, across any terrain, and for two hours at night in camp (a total of 10 hours of holding a length of steel at tension) with no problems whatsoever. And no gaps in that sword holding of longer than 5 seconds.

Personally, I think that is naughty word.

Also yes. That's what a readied action does. It interrupts when the trigger happens and you get to go first.

Okay, I'm going to have to break this down into piece by piece mechanics, otherwise you are never going to understand this point.

To have a readied action, you have to use your action every single turn to reapply your readied action. Over the course of a 2 hour watch that would be... 1,200 turns of combat. And during that entire time during their watch, they never once step more than five feet away from the bound and gagged individual. They also, during their watch, never once use their action to use perception to look for any threats.

After all, what we have in practice is two readied actions. To put this in an example, let us say you have two archers pointing arrows at a door. Each one has readied an action to shoot the first person they see, and each shot if it lands will kill the other archer. The door dissolves. Who shoots first? They both have their trigger activate at the same time, who resolves first? Generally, it would be a dex check (aka initiative)

The Psion has a readied action for when the guard gets distracted. They are specifically looking for a moment where the guard can't use their readied action to attack them. And if they start casting because of that readied action, then they should logically finish casting first, but it will probably be a dex check to see who goes first. Because both triggers happen nearly simultaneously.

Trade off. Fighter does it, then rogue does it, and then bard does it. Then rest.

Um... huh?

This is during a long rest. An 8 hour long rest. So, each watch is two hours. So every two hours you would need someone to trade off, but that does not change the fact that you need to keep your attention on them for two hours. Unless you do hour long watches, but again, that is still not easy.

There are literally thousands of reasons why you didn't kill them in combat, but would if they continued to attack you. Pick one.

There are literally thousands of reasons why you can't kill them. Pick one.

So first, no. Only rare(if any) NPCs have class levels. NPC casters just cast similar to PC classes. They don't actually possess class levels. Second, I'm talking about hit dice to regain hit points, not hit dice you roll for their original hit points. That should have been clear when I referenced rolling hit dice to heal.

So first, no. Being rare does not meant they don't exist. Hence why they are rare, not nonexistent.

Second, you seem to forget how Hit Dice work. I'll go ahead and quote the PHB:

Your character’s hit points define how tough your character is in combat and other dangerous situations. Your hit points are determined by your Hit Dice (short for Hit Point Dice).

At 1st level, your character has 1 Hit Die, and the die type is determined by your class. You start with hit points equal to the highest roll of that die, as indicated in your class description. (You also add your Constitution modifier, which you’ll determine in step 3.) This is also your hit point maximum.

Record your character’s hit points on your character sheet. Also record the type of Hit Die your character uses and the number of Hit Dice you have. After you rest, you can spend Hit Dice to regain hit points (see “Resting” in chapter 8, "Adventuring").

So, what do we see here?

The player gets hit dice. These hit dice determine their "original hp" as you put it. Those exact same hit dice are then recorded, and used during resting to recover hp.

So, either monster hit dice work under a completely different set of rules (which is never stated anywhere, and makes no sense) or the hit dice of a monster can be spent like any other hit dice in the game. This is additionally supported by the fact that monsters have abilities that refresh on a short rest. The point of Short Rests are to restore hit points by spending hit dice, something that would then clearly be expected for the monster to also be capable of doing.

Unless you can somewhere find a rule that states monsters cannot restore hit points during short or long rests.

Don't assume. Use RAW. There are no class levels involved in any NPC stat blocks in the MM. Monsters/NPCs and PCs do not use the same rules unless the DM chooses that option when creating the NPC. As you note in your hit point quote, RAW does not give monsters hit dice to heal with. It only gives them initial hit points.

They don't need to specify that, because they have hit dice and you can spend hit dice to heal during a short rest. There are not two different types of hit dice.

Also, I am fully prepared to use RAW to determine the number of hit dice in the Psion NPC statblock, as soon as you show me a RAW Psion NPC Statblock. Until then, I think my use of an analogous creature (the statblock for a Mage) is fair game for a rough estimate.

And I break posts apart like that because I have ADHD and if I don't start responding to portions as I encounter them, I will forget a lot of what I have to say. I'm sorry if it's annoying to you, but it's the way I have to respond.

That is a legitimate reason to do it, and I apologize if my call out made you uncomfortable, but I have expeirenced this being used to attack an argument line by line, making it seem like the argument is weaker than it is.

Unless it's really dim light, there's virtually no way to miss exposed brains in a swarm of rats. Even in a single rat it would be pretty easy to notice.

Sure, if the entire swarm ran past you, but they wouldn't do that.

They might be running up above you, where you can't see the top of their head.
They might be just poking their snout out of a rat hole, where you can't see the top of their head.

They might, maybe notice if a single rat ran past them, that it has a pink streak on its head. But if it just darts past without stopping, would you really notice it is a brain? I've seen rodents dart past people, and I couldn't even tell if they had tails, or the snouts, they were just a blur of color going past. Yes, adventurers have better reflexes and better perception than me (most likely) but it is still a difficult enough task that I would at least roll or look at their passive perception, not just tell them outright.

 

[Maxperson]

You are welcome to that opinion, but it is based on no evidence, and countered by Tasha's releasing Psionic spells.

The bolded part is objectively wrong. The MM creatures are in fact evidence, as are the UA articles. You can disagree with what the evidence means, but you will be objectively incorrect to state that it isn't evidence.

As for Tasha's, that's not evidence of anything contrary to what I'm saying. Spells with a psionic component are not psionics. They are spells. Spells cannot contradict what I'm saying about psionics.

Also, he additionally said he was neutral on components. So he would be fine with components in Psionic powers (VSM to be specific of what I am talking about) so, the person whom you insisted completely agrees with your point of view, disagrees with your core and fundamental argument.

He said he was neutral on components and then went on to say this immediately after, "I would prefer they stick to tradition and not use them however I don't feel that's a key component of what makes them different from magic."

That's not a neutral statement. He wants no components, but would be okay with them if they show up.

1) I am allowed to not be convinced by your ways of balancing, especially since

2) Making the class abilities weaker does not solve the problem I put forth. In fact, it does not matter at all to the problem I put forth. Sort of like solving the problem of "I am worried my house will catch fire" by giving me car insurance. Yes, that is a good thing for me to have, but it sort of does nothing for the problem about the house.

And I'm not convinced that your problem is a problem. At least not a general one that needs to be fixed. I can believe that it's a problem personal to you, but that doesn't mean that it needs a great amount of attention. I'm working to balance the class for the most people, and I don't think what you bring up is going to be a significant part of most people's games.

Well, I'm glad that you can hold a 3 lb length of steel to someone's neck while on an 8 hour march, across any terrain, and for two hours at night in camp (a total of 10 hours of holding a length of steel at tension) with no problems whatsoever. And no gaps in that sword holding of longer than 5 seconds.

The Psion has less than 5 hit points, and probably only 1 or 2. He also isn't gaining any hit points due to no long rests. Use a dagger.

To have a readied action, you have to use your action every single turn to reapply your readied action. Over the course of a 2 hour watch that would be... 1,200 turns of combat. And during that entire time during their watch, they never once step more than five feet away from the bound and gagged individual. They also, during their watch, never once use their action to use perception to look for any threats.

So have a 2nd PC awake. Also, there are no actions like that outside of combat. I used readied action, because it was the easiest way to convey what the PC is doing. You just tell the DM that if he twitches as if to cast a spell, you slit his throat. If the Psion decides to be an idiot and actually attack a group while at under 5 hit points, he deserves what he gets.

After all, what we have in practice is two readied actions. To put this in an example, let us say you have two archers pointing arrows at a door. Each one has readied an action to shoot the first person they see, and each shot if it lands will kill the other archer. The door dissolves. Who shoots first? They both have their trigger activate at the same time, who resolves first? Generally, it would be a dex check (aka initiative)

The Psion has a readied action for when the guard gets distracted. They are specifically looking for a moment where the guard can't use their readied action to attack them. And if they start casting because of that readied action, then they should logically finish casting first, but it will probably be a dex check to see who goes first. Because both triggers happen nearly simultaneously.

Okay. The Psion sees the guard is distracted and begins casting a spell, at which point the guard notices and his readied action triggers, interrupting the Psion and knocking him to 0. Or just keep the bloody Psion knocked out and carry the unconscious body.

This is during a long rest. An 8 hour long rest. So, each watch is two hours. So every two hours you would need someone to trade off, but that does not change the fact that you need to keep your attention on them for two hours. Unless you do hour long watches, but again, that is still not easy.

So then keep the guy unconscious.

So first, no. Being rare does not meant they don't exist. Hence why they are rare, not nonexistent.

Second, you seem to forget how Hit Dice work. I'll go ahead and quote the PHB:

Your character’s hit points define how tough your character is in combat and other dangerous situations. Your hit points are determined by your Hit Dice (short for Hit Point Dice).

So, what do we see here?

The player gets hit dice. These hit dice determine their "original hp" as you put it. Those exact same hit dice are then recorded, and used during resting to recover hp.

So first, the only time an NPC has class levels is if the DM chooses to give them to the NPC. Secondly, the NPC stat blocks aren't even PC classes. The Archmage has no levels of wizard, despite having lots of wizard spells. Monsters don't get healing hit dice.

You're looking in the wrong book for the rules, by the way. You need to be looking in the Monster Manual, not the PLAYERS Handbook.

This is additionally supported by the fact that monsters have abilities that refresh on a short rest. The point of Short Rests are to restore hit points by spending hit dice, something that would then clearly be expected for the monster to also be capable of doing.

This supports me, not you. Short rest abilities are called out in the stat block. Hit dice are not mentioned there.

Also, I am fully prepared to use RAW to determine the number of hit dice in the Psion NPC statblock, as soon as you show me a RAW Psion NPC Statblock. Until then, I think my use of an analogous creature (the statblock for a Mage) is fair game for a rough estimate.

Sure. The mage has no wizard levels, though. Or any levels at all.

That is a legitimate reason to do it, and I apologize if my call out made you uncomfortable, but I have expeirenced this being used to attack an argument line by line, making it seem like the argument is weaker than it is.

No worries. You didn't make me uncomfortable. I was just explaining why I do it. I respond to points made as I read them so I don't forget. There's no ulterior motive to make arguments weaker.

They might, maybe notice if a single rat ran past them, that it has a pink streak on its head. But if it just darts past without stopping, would you really notice it is a brain? I've seen rodents dart past people, and I couldn't even tell if they had tails, or the snouts, they were just a blur of color going past. Yes, adventurers have better reflexes and better perception than me (most likely) but it is still a difficult enough task that I would at least roll or look at their passive perception, not just tell them outright.

If it just ran past you might or might not notice it. That's what perception is for. At the least you'd probably note something weird with its head.

 

[Chaosmancer]

I don't have time to respond to all of this, but a few things

So have a 2nd PC awake. Also, there are no actions like that outside of combat. I used readied action, because it was the easiest way to convey what the PC is doing. You just tell the DM that if he twitches as if to cast a spell, you slit his throat. If the Psion decides to be an idiot and actually attack a group while at under 5 hit points, he deserves what he gets.

Okay. The Psion sees the guard is distracted and begins casting a spell, at which point the guard notices and his readied action triggers, interrupting the Psion and knocking him to 0. Or just keep the bloody Psion knocked out and carry the unconscious body.

So then keep the guy unconscious.

"If he twitches" while casting a spell that requires no body movement or verbal components. So... he can be perfectly still and he;ll cast by having himself light up.

Also, I love how the guard is immediately able to use his readied action first, to interrupt the readied action of the Psion. Can the psion instead have a readied action to counter the readied action of the guard, then twitch suspiciously by trying to move triggering the guards attack and then the Psion interrupts with his readied action (trigger if the guard goes to attack me) and complete his readied action first?

Or is this just DM fiat that stabbing someone is faster than thinking a spell into existence?

And, sure, knocking him unconscious every 1 to 4 hours (because you wake up in 1d4 hours) is a potential solution. But it is still not something that is in anyway reasonable to accomplish.

So first, the only time an NPC has class levels is if the DM chooses to give them to the NPC. Secondly, the NPC stat blocks aren't even PC classes. The Archmage has no levels of wizard, despite having lots of wizard spells. Monsters don't get healing hit dice.

You're looking in the wrong book for the rules, by the way. You need to be looking in the Monster Manual, not the PLAYERS Handbook.

So, you are going to insist that there are Hit Dice and that there are Hit Dice, and Hit Dice let you heal during a short rest, but Hit Dice don't. All because they did not reprint the rules for Hit Dice in the Monster Manual.

I suppose Longswords in the Monster Manual are different that Longswords in the PHB? Plate Mail in the Monster Manual is different than Plate Mail in the PHB? Fireball in the Monster Manual is different than Fireball in the PHB?

Because, To reiterate the rules given for Hit Dice in the player's handbook. You keep track of the type of Hit dice used to determine your Hp, and the number of Hit Dice you use to determine your hp. Period. End of Sentence. End of thought. New Sentence. New thought. After you rest you can spend Hit Dice to recover hp as covered in the section on resting.

The final sentence is not saying you gained a separate set of HD for use in healing, it is explaining that you keep track of those same HD for use in healing.

In fact, if your logic here were correct, and monsters cannot use their Hit Dice during resting, then they also can't take a long rest and recover their HP. Because those rules are not in the monster manual. You would deal 20 pts of damage to a monster, and come back a week later to find that monster still missing 20 hp, because they have no rules for recovering HP.

Or we can assume that the monsters can take long and short rests like everyone else, and Hit Dice are the same as Hit Dice, not some new mechanic called Hit Dice.

If it just ran past you might or might not notice it. That's what perception is for. At the least you'd probably note something weird with its head.

Right, this is exactly what I said. You might or might not notice it. You probably would need a perception test. However, since a perception test requires actively looking, the DM might simply use their passive perception, since they are not paying any special attention to the rats.

I am so glad that after three or four posts arguing this with you, you finally came around to telling me exactly what my starting position was.

 

[Maxperson]

"If he twitches" while casting a spell that requires no body movement or verbal components. So... he can be perfectly still and he;ll cast by having himself light up.

Also, I love how the guard is immediately able to use his readied action first, to interrupt the readied action of the Psion. Can the psion instead have a readied action to counter the readied action of the guard, then twitch suspiciously by trying to move triggering the guards attack and then the Psion interrupts with his readied action (trigger if the guard goes to attack me) and complete his readied action first?

Or is this just DM fiat that stabbing someone is faster than thinking a spell into existence?

Do you have a special rulebook where spells are faster than 1 action? Because in my book the vast majority of spells are just the same speed as weapons, whether you have to concentrate on them or speak them.

And, sure, knocking him unconscious every 1 to 4 hours (because you wake up in 1d4 hours) is a potential solution. But it is still not something that is in anyway reasonable to accomplish.

Why not? It's easy peasy.

So, you are going to insist that there are Hit Dice and that there are Hit Dice, and Hit Dice let you heal during a short rest, but Hit Dice don't. All because they did not reprint the rules for Hit Dice in the Monster Manual.

Spells have levels and so do PCs. They aren't the same level. Monster hit dice are not the same as PC hit dice.

I suppose Longswords in the Monster Manual are different that Longswords in the PHB? Plate Mail in the Monster Manual is different than Plate Mail in the PHB? Fireball in the Monster Manual is different than Fireball in the PHB?

As soon as you can show me the d8 hit die Wizards in the PHB, I'll start believing that an Archmage is a Wizard. Oh, and explain how a core Archmage Wizard doesn't have basic Wizard abilities like Arcane Recovery or an Arcane Tradition. Until then, I'm going to continue to understand that monsters and PCs use different rules and don't have PC class levels, and hit dice for healing are for characters with class levels.

 

[Paul Farquhar]

Whereas I would say "you see a bunch of rats with exposed glowing brains", because that is a really obvious thing that the PCs would definitely notice but the players have no way of knowing unless I tell them. And if a GM tried to pull "you didn't say you looked at the rats specifically" with me I would be unimpressed to say the least.

_
glass.

If the brains glow at all (and that assumption is only based on the illustration, their is nothing in the text to indicate that) it would be only when their powers are active. Rats are tiny, their brains are less than 1 cm across, it was dark, it was a location where you would expect to find rats, cranium rats are highly intelligent and where largely trying to stay hidden, and even so, I allowed a passive nature check (which they failed) for the party to notice something unusual about them. My players where quite happy that I had given them a sporting chance.

 

[Paul Farquhar]

They are frequently depicted with gestures, not because the gestures are necessary, but because it adds to the artistic/dramatic value of the medium. Comics, TV and movies are a different medium than roleplaying games.

They are depicted with gestures for exactly the reason material components are required in D&D - so the person watching can tell that a certain character is using their powers.

Intentionally concealing power use would require more concentration, so works fine with sorcery points-subtle spell.

Significantly more powerful, yes. Broken, no. And all you need are displays and you can in fact have no components with no increase in combat power.

In 5e D&D a display is a component. That's how it's represented in terms of game mechanics. It is explicit in 5e rules that if you cast a spell without components (i.e. subtle spell) an observer cannot tell that the character is casting a spell.

No components = no display

I think it's very likely that Tasha's will include a sidebox suggesting refluffing components if the character is intended to be psionic.