Arcane Perfectionist [Feat]

[Yakk]

Requires the ability to cast at least 1 spell. Your extensive spellcasting practice and attention to detail unlocks new power from spells. When you start to cast a spell with a casting time of 1 action, you can choose to extend the casting time to 2 actions. Doing so requires concentration, but you can concentrate on another effect while doing so. If your concentration is broken the spell fails, and any spell slot used is wasted. In exchange, the spell becomes more potent. Any saving throws against the spells effects are at disadvantage, all attack rolls the spell grants are at advantage, and any damage dice rolled are doubled in number.

[JNAProductions]

First off, this works on Divine spells too.

Second off, this is brutally overpowered. Even ignoring cheesing it out (two levels in Fighter for Action Surge means you can, once per short rest, make any spell do double damage, with advantage on attack rolls and disadvantage on saves) it's still far too good.

What I would do is this:


Arcane Perfectionist
Requires the ability to cast at least one arcane spell

When casting a spell from a spell slot with a casting time of one action, you may choose to extend the casting time to make it more potent. Spend an additional action casting the spell to increase the effective spell level by one, to a maximum of your proficiency bonus. As usual, casting a spell in this fashion requires concentration.

At level eleven, casting a spell in this fashion no longer breaks concentration on a spell you are already concentrating on, though you still lose the spell if you fail a concentration save while casting it.

[Yakk]

Hmm. I should make it a 12 second casting time (two turns) instead of 2 actions.

Then action surge won't let you do it in one turn. You have to spend 1 action on each of those turns to cast the spell.


Requires the ability to cast at least 1 spell. Your extensive spellcasting practice and attention to detail unlocks new power from spells. When you start to cast a spell with a casting time of 1 action, you can choose to extend the casting time 2 rounds (12 seconds). Each turn you must spend 1 action to cast the spell, and it finishes when you spend the action on the 2nd turn. Doing so requires concentration, but you can concentrate on another effect while doing so. If your concentration is broken the spell fails, and any spell slot used is wasted. In exchange, the spell becomes more potent. Any saving throws against the spells effects are at disadvantage, all attack rolls the spell grants are at advantage, and any damage dice rolled are doubled in number.

[JNAProductions]

Still brutally overpowered.

[Yakk]

So, I am ok with the "level 3 spell slot produces a 16d6 fireball with disadvantage on saves"; your DPR is only modestly increased (by the disadvantage on saves).

I could make the DPR remain flat by saying you can either double damage dice, force disadvantage on saves, or grant advantage on attack rolls. That would make DPR relatively flat on damage spells. And on save-or-suck it would be akin to casting the spell over 2 rounds (so, higher spell slot efficiency... assuming you aren't interrupted).

I'm concerned about things going further than this.

You cast a concentration spell for 2 rounds, then repeat the double damage dice each round. So sunbeam becomes 12d8 per round after a 1 round delay. In a 3 round fight this is 24d8 instead of 18d8, a 33% increase. In a 4 round fight, 36 instead of 24 (50%). 5 rounds, 48 instead of 30 (60%)

Spirit Guardians becomes a 6d8 aura if you manage to cast it, and you could pre-cast this spell. That is probably too far.

So how about:
1. You either double damage dice, or you have advantage on attack rolls and force disadvantage on saves.
2. It does not work on spells that require concentration.

Now it gets really close to "save spell slots" not "increase effectiveness per round" (except insofar as being able to use more level 3 slots in a fight).

Are there any extended-duration non-concentration standard-action spells I don't know about?

[JNAProductions]

Honestly, I'm not as worried about damage as I am a Hold Person/Monster with disadvantage on every single saving throw. (Though the massive saving on spell slots IS an issue.)

For reference, at level 5, you're usually rocking DC 13-15. If VHuman, easily 15. If High Elf or Gnome or something, 14. If anything else, 13.

Against someone with +1 to Wisdom saves, you've got a just over 20% chance of making the DC 13 save.
You've got just over a 12% chance of making the DC 15.

Let me try another tack-would you ever NOT take this feat as a caster?

[AvatarVecna]

Arcane Perfectionist
Prerequisite: the ability to cast spells
Effect: Whenever you cast any spell that takes only one action to cast, you can choose to immediately cast it a second time. If you do so, the second casting doesn't cost a slot.

[Yakk]

While ruling out concentration makes Hold spells not work... let's compare.

Enemy has a +2 save bonus. You have a DC 14 check.

Without feat, using 2 spells and 2 actions:

Round 1: 45% chance of being held; accumulated 0.70 rounds of holding
Round 2: 20.25% chance still held; +35.8875% chance of from 2nd casting; 56.1375%. Accumulated: 1.01 rounds of holding.
Round 3: (9.1125% + 5.011875%) + 16.149375% chance of being held; 30.27% Accumulated: 1.31 rounds
Round 4: 4.100625% + 2.26% + 9.5225625% chance of being held; 15.88%. Accumulated: 1.47 rounds

Without feat, using 3 spells and 3 actions:

Round 1: 45% chance of being held; accumulated 0.70 rounds of holding
Round 2: 20.25% chance still held; +35.8875% chance of from 2nd casting; 56.1375%. Accumulated: 1.01 rounds of holding.
Round 3: (9.1125% + 5.011875%) + 16.149375% + 31.38% chance of being held; 61.65% Accumulated: 1.62 rounds
Round 4: 4.100625% + 2.26% + 9.5225625% +14.121% + 5.2371% chance of being held; 35.24%. Accumulated: 1.98 rounds

With feat, using 1 spell and 2 actions:
Round 1: 0% chance of being held
Round 2: 69.75% chance of being held; accumulated 0.6975
Round 3: 48.65% chance of being held; accumulated 1.18
Round 4: 33.93% chance of still held; accumulated 1.52

With feat, using up to 2 spells and 3 actions:
Round 1: 0% chance of being held
Round 2: 69.75% chance of being held; accumulated 0.6975
Round 3: 48.65% + 23.11% = 71.76% chance of being held; accumulated 1.41
Round 4: 33.93% + 6.87% + 10.40% = 51.2% chance of still held; accumulated 1.92

So the "perfected" casting doesn't outdo the "just cast it" in turns of rounds-held until round 4. If they burn 3 actions and the same number of spell slots, it catches up at round 3. But if the non-perfected caster just spams hold person 3 times (same number of actions) it stays ahead of the perfected caster using 3 actions.