D&D 5E Power Word: Stun and stunning strike level confusion

[Perun]

I was poring over the higher level (6+) spells last night, trying to plan ahead which would make for a good choice for my sorcerer's repertoire, and I stumbled over power word: stun. And I'm a bit confused... monks get stunning strike as an ability at 5th-level. It uses up a ki point, a finite resource -- but the one that recharges at short rest. Power word: stun, OTOH, is an 8th-level spell, meaning it's a 1/long rest resource (I can't think of a way to get two 8th-level spell slots at the moment, but I'm not very well versed in the rules).

PW:S is, theoretically, of infinite duration, provided the target keeps failing their saving throw (DC 19, with spellcasting ability modifier +5). But then, a 15th-level monk theoretically has 15 stunning strike attempts per short rest, and at that level his DC should be close, if not identical, to that of the PW:S caster.

Now, we're still around level 10 in our campaign (so far my only 5e experience), and I haven't seen monk in actual play, so there could very well be a lot that I'm missing...

Is there a general opinion on this? Does PW:S come too late in the game, or do monks get stunning strike too early in the game? Is one over-/underpowered compared to the other? Or do the (apparently) small differences between the two keep them at just the right levels for both to be fully effective and level-appropriate?

 

[mortwatcher]

PW:S ... and pretty much all the other PWs, are bad player spells, so I would avoid that one
they can find some use on big baddies against players

 

[Quartz]

PWS is cast at range. The Monk has to get up and personal. I wonder if it could be a deadly combo: the sorceror casts PWS (likely metamagicked with Distant Spell) then the monk rushes in to keep the BBEG stunned.

 

[MarkB]

There's also the factor that Stunning Strike requires two successful rolls to pull off - first you have to hit, then your opponent must fail their save.

 

[Dausuul]

The key difference is that power word stun does not grant an initial save. You are guaranteed to get 1 round out of it. That is a Very Big Deal - one round of stun is often a death sentence. Moreover, you typically want to use stun effects on big boss monsters, which often have a) good Con saves and b) Legendary Resistance.

(Also, the power words are generally on the weak side for their level. They'd be a lot better if they gave you some way to determine before casting if the target was "within range.")

 

[UngeheuerLich]

The key difference is that power word stun does not grant an initial save. You are guaranteed to get 1 round out of it. That is a Very Big Deal - one round of stun is often a death sentence. Moreover, you typically want to use stun effects on big boss monsters, which often have a) good Con saves and b) Legendary Resistance.

(Also, the power words are generally on the weak side for their level. They'd be a lot better if they gave you some way to determine before casting if the target was "within range.")

I really can't stress how valuable a single round of stun is..

 

[TheCosmicKid]

I'm also pretty okay with a caster not being able to do an iconic monk thing as early or as well as a monk.

 

[ad_hoc]

PW: Stun doesn't have a Saving Throw.

Not even Legendary Resistance can stop it.

Now, the big downfall of the spell is the HP threshold of 150. That's not so bad as a way to finish a creature off. If you stun an ancient dragon for example then the party can deal out that 150 dmg in the next round.

The issue is guessing when the creature is down to that many HP. You're going to want to overshoot it just in case, when at a certain point, it's not worth it anymore.

 

[Perun]

I can see the (extraordinary) benefit a round of stun would be against a BBEG. However, after reading through the replies, and going through this thread, I have concluded that the power word spells are Not Very Good Spells At All. IMO and all that, of course.

Those are the highest-level spells in the game, 8th (pw: stun) and 9th level (pw: kill) -- highly valuable and extremely limited resources at the top-tier level of the game, yet their efficiency entirely depends on the remaining hp the target has. If pw: stun had an added sentence, something along the lines of:

You speak a word of power that can overwhelm the mind of one creature you can see within range, leaving it dumbfounded. If the target has 150 hit points or fewer, it is stunned. If the target has 151 hit point or more, it must make a Constitution save, or be stunned.
The stunned target must make a Constitution saving throw at the end of each of its turns. On a successful save, this stunning effect ends.

that would have made the spell reasonably usable. It's not that I think the spell is completely useless, it's just that I have a hard time wrapping my mind around the fact that the spells of the highest order in the game have to be cast on already weakened opponents in order to have any effect.

In fact, it think that if I ever return to DM-ing, I might add that as a house-rule (along with similar text for pw: kill, which lets the spell do 100 hp of damage to a target with 101 or more hp).

 

[Quartz]

Those are the highest-level spells in the game, 8th (pw: stun) and 9th level (pw: kill) -- highly valuable and extremely limited resources at the top-tier level of the game, yet their efficiency entirely depends on the remaining hp the target has.

How often does a 15th-20th level wizard have 150 HP or more?