5E #BOOMBIGGEN - 2 action spellcasting

Inspired by a hashtag over in the "remove damage cantrips" thread, I though how we could make spells hurt more while maintaining some semblance of balance. This is my attempt:


Most spells (includign cantrips) that take 1 action to cast now take 2 actions. Casting a 2 action spell requires concentration, but you can maintain concentration on another spell or effect while doing so. If your concentration is broken, the spell is lost and its slot is wasted. You can cast other spells while casting a 2 action spell with a bonus action or reaction casting time, but only if the components of the spells do not overlap.

When you cast a spell as a 2 action spell, its save DC and spell attack accuracy is increased by 2, and its damage or healing dice are doubled. Quicken spell can be applied to 2 action spells, but then those modifiers are not applied to the resulting bonus action spell.

If you fail to use your next turn's action to finish a 2 action spell, the spell fails and any slot used is wasted.

Exceptions: Spells that do not require a save and have no spell attack roll and do not deal damage and do not heal still only require 1 action to cast. As an example, Dimension Door. Polymorph can require a save, so it is a 2 action spell even when cast on an ally.

Spells whose casting time is a bonus action or reaction are unchanged.

Example: A level 5 wizard with 18 int casting fireball has a 17 save DC and 16d6 (avg 56) damage. Firebolt has a +9 spell attack roll and deals 4d10 (22 avg).

His friend the level 5 18 cha warlock can EB for +9 @ 2d10+4 x2 (30 avg).

The dragon sorcerer can quicken firebolt (2d10+4, 15) start casting fireball, finish fireball next turn (16d6+4, 60 avg), then quicken firebolt for (2d10+4, 15).

Charlie the Cleric casts a 3rd level mass healing word. It is unchanged, as a bonus action spell, and heaks for 1d4+4 (6.5 average). But later she casts a 3rd level cure wounds or a 5th level mass cure wounds, either heals for 6d8+4 (31 avg) on each target but takes 2 actions to cast.

Design Notes:
This increases efficiency of spell slots generally if you can avoid having concentration disrupted. Damage per action remains very similar. +2 ATK/Save is intended to boost reliability to make up for variance increase (which hurts players) and keep save-or-suck from completely sucking. Legendary resists are probably still a problem, as forcing a save is twice as hard now.
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It will generate a lot of frustration due to battle field change.
it is sometimes hard to place area spell, it will now be pure guess. Not good.
I'd say there are a number of issues here. Note that I haven't read the thread you mentioned, so I'm unfamiliar with any issues that may have been raised there.

Firstly, this is a rather large nerf to casters. Not only can they only do half as much in a given combat, but it is back-loaded. If I try to polymorph the fighter because he's low on HP, in two turns he could be unconscious (in which case polymorph won't help him) or dead (in which case it definitely won't help him). Sure, technically you've kept their damage roughly the same, but damage isn't really what casters excel at, IMO.

Additionally, you've buffed out of combat healing tremendously for no reason I can discern. If the goal was to eliminate damage cantrips, what does that have to do with healing? There are no healing cantrips. If the healers have to spend twice as long to heal someone, that means they have less opportunities to deal damage, meaning they do less damage. Sure the healing is technically doubled, but since it is spread across double the time it's functionally the same (meaning it won't keep pace with damage). Also, since only the dice is doubled, healing isn't even doubled, since much of the potence of healing spells comes from non-dice, such as the casting modifier or the entirely flat healing of the Heal spell.

Finally, this can potentially be gamed for huge benefit sans drawbacks. Know you're getting into a fight? Spend a round charging up your spell before the fighter kicks in the door! It's like getting a bonus caster-only surprise round, since you can lob a supercharged double-fireball (or whatever) on the first round of combat.

It did, however, give me inspiration for a new kind of charged damage cantrip. These cantrips would be cast similarly to how you've outlined above. Two actions, which can be disrupted. The cantrips would deal one die type lower than their non-charged variants. However the second action would triple the dice. On their turn, before spending the second action, the caster could choose to release the spell and deal the base damage. This might be useful if you need damage NOW, or if on your second turn you need your action to cast a different spell.

For example, Overclocked Firebolt would function much like Firebolt but would deal only d8 damage. You can cast it with a single action at 1st level to deal 1d8 damage. However, if you spend a second action casting it, it deals 3d8 damage.


I imagine that spellcasting in this fashion would all too often resolve the way that True Strike tends to, as illustrated here:



I imagine it would be mainly used for ambushing unaware baddies, rather than during combat. Most fights change too much every round to 'Hold' a spell without you considering your options again. What about the targeting and placement of AOE? Do i do it this round or the next?

Its still too broken an idea. Your wizard/Sorcerer can hide 120ft away to charge up, and most fights will be over before it started. A cleric can charge up his Guiding bolt to deal 8d6 damage, and it becomes 16d6 damage on a crit. Whats the point of martials anymore?
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Since playing PF2 I wanted to make spellcasting more fun and dynamic in 5e.

My idea goes like this:

You either cast your spell normally.

Or you go double or (less than) nothing.
Which means you overdrive your spell and roll a flat check to see if the overdrive succeeds. In case it succeeds your spell becomes roughly twice as powerful.
If it fails you roll on the spell fail table (I already use it for spell interruption on my table) i.e. the spell backfires. On failure you also still use spellslots.

This way the damage output stays roughly the same, but it adds a cool decision for the casters of going full risk and deal with the consequences.
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So the healing is a good point; because in practice healing in 5e is often done out of combat, this does make it significantly more efficient with much less downside than the damage increase on spells.

Possibly I should just restrict this to spells that deal damage. I'm a bit afraid that would mean that minor damage riders (like on dissonant whispers) act as a serious nerf.


I like idea as an option. You have the choice to cast a spell normally or as a 2-action cost with enhanced effects.
So the healing is a good point; because in practice healing in 5e is often done out of combat, this does make it significantly more efficient with much less downside than the damage increase on spells.

Possibly I should just restrict this to spells that deal damage. I'm a bit afraid that would mean that minor damage riders (like on dissonant whispers) act as a serious nerf.
It does, but look at it this way. You're un-nerfing spells that didn't benefit much or at all from this change (such as polymorphing an ally). Essentially, you're rolling back a nerf from a lot of spells (where a +2 DC is, at most, a token benefit when compared to a two round casting time and all that encompasses). Dissonant Whispers was just as nerfed under the original version you proposed.

One option would be to go through the list of damage spells and determine which spells this applies to, leaving off spells with minor damage like DW.

Mind you, I think my other objections still apply. Back-loading caster damage is less than ideal, considering it isn't broken now. And any time a caster has a round to prepare for battle, their opening round is going to be obscene (effectively 2 rounds of damage for the price of 1).

On the one hand this does push wizards towards a more wizardly approach to combat, where they try to know what is coming in order to annihilate it. On the other hand, that is not necessarily synergizing with the rest of the party. The rest of the group might not want a slow, methodical approach where the wizard ends many encounters before they can begin. 16d6 (56) damage at level 5 is a sizable opener, particularly for an area of effect.


I'm not 100% sold on the idea, but with a bit of tweaking maybe it could work. But one thing that would help...

Let sorcerers simply prepare to cast a spell of x level, and then on the next turn they can cast any spell of that level (included upcasting lower level spells). Flexible casters, yo.
This is already a sorcerer stealth-buff. Both because of still spell (allowing counterspells to be cast at the same time as other spells) and other metamagic working really well with this.

The quicken, cast, quicken pattern gets 3 spells off over 2 rounds (one #BOOMBIGGEN ed).

Among other things, this means the sorcerer can interrupt enemy spellcasting really easy.

It does change the tactical situation with spellcasting. Ambushes become important. Failing that, having a defensive line matters a lot. Warcaster and Constitution proficiency is awesome.

I do understand this changes spellcaster gameplay significantly. It is interesting that it does so in ways that make spellcasters both better and worse.


Anyhow, as people have said they would prefer this as an option instead of a requirement, how about a feat?

Focused Spellcasting Requires: ability to cast at least one spell.

When you cast a spell that requires 1 action to cast, you can choose to focus and increase its casting time to two actions. You can concentrate on this spell cast at the same time as concentrating on maintaining another effect. If your concentration is broken while casting, the spell fails and any spell slot you used is lost. However, if you finish casting a spell you have focused on, the spell is more powerful. All saving throws against the spells effects are at disadvantage, you have advantage on all attacks the spell grants, and damage dice from the spell are doubled in number.
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