Warcaster and using a spell as a AoO.

[Desiani]

So me and my DM have a very confusing situation. I tried using Sacred flame as an AoO to attack a zombie.

He was saying that it provokes an AoO because I am casting in melee. I say it doesn't because its a feature of a feat. We have scoured the PHB for an answer and I come to yall to get opinions.

Does casting a spell because of warcaster feat incure an AoO or does it not?

Thank you for your help.

[NNescio]

So me and my DM have a very confusing situation. I tried using Sacred flame as an AoO to attack a zombie.

He was saying that it provokes an AoO because I am casting in melee. I say it doesn't because its a feature of a feat. We have scoured the PHB for an answer and I come to yall to get opinions.

Does casting a spell because of warcaster feat incure an AoO or does it not?

Thank you for your help.

In 5e, casting spells (or using a ranged weapon) in melee DOES NOT provoke OAs. This is unlike in 3.5e, where they do provoke AoOs.

Warcaster does not factor into this. You can still cast spells in melee without provoking OAs, with or without Warcaster. Ranged attacks (including both weapon and spell attacks) do suffer disadvantage when aimed at targets 5ft away though, but spells that don't involve attack rolls like Sacred Flame don't care about this. Same goes for melee spell attacks.

The key exception is when you're up against a creature with the Mage Slayer feat.


...When a creature within 5 feet of you casts a spell, you
can use your reaction to make a melee weapon attack
against that creature. ...

This is technically not an OA (so if he also has Sentinel, the attack doesn't reduce your speed to 0 because it is not an OA), but a creature within 5 ft of you with Mage Slayer can use his reaction to attack you if you cast a spell, among other benefits (to him, not you). Also, Mage Slayer doesn't care if you have War Caster or are otherwise casting a spell as a reaction.

So, unless the zombie has the feat, no, not really.

Remember, in 5e, unless feats or creature statistics say otherwise, only moving out of a creature's reach (and not moving out of a creature's threatened square, so you can circle around your opponent) provokes OAs.

Relevant rules:


OPPORTUNITY ATTACKS
In a fight, everyone is constantly watching for enemies to drop their guard. You can rarely move heedlessly past your foes without putting yourself in danger; doing so provokes an opportunity attack. You can make an opportunity attack when a hostile creature that you can see moves out of your reach. To make the opportunity attack, you use your reaction
to make one melee atlack against the provoking creature. ...

No other circumstances provoke OAs (unless feats, class features, creature traits, or other specific details overrules this general rule). Only moving out of a creature's reach while he can see you does. Casting spells, attacking with a ranged weapon, attacking with an unarmed weapon, moving out of threatened squares (but not completely out of a creature's reach), shoving (5e's Bull Rush), the Help Action (5e's Aid Another), drinking a potion, lighting torches, stabilizing a dying creature, reading scrolls, innate spellcasting (5e's spell-like ability), etc. DO NOT provoke OAs, unlike in 3.5, where they do provoke AoOs.

[Desiani]

Thank you! :)

[NNescio]

Thank you! :)

You're welcome.

[TopCheese]

The first question of any game should be "are you using house rules". Perhaps the DM uses a houserule. Also many DMs modify monsters to challenge and surprise players.

But then again most screw ups come from the side of the screen with the most to keep track of, this isn't really something worth freaking out about but do bring it up outside of the game.

[Desiani]

The first question of any game should be "are you using house rules". Perhaps the DM uses a houserule. Also many DMs modify monsters to challenge and surprise players.

But then again most screw ups come from the side of the screen with the most to keep track of, this isn't really something worth freaking out about but do bring it up outside of the game.

No one was really freaking out... we are comming from 3.5 and are doing a fairly by the book game so we can get used tl the differences. This is why i asked :p

[Joe the Rat]

You wouldn't be the first group to make that mistake. In one of our first "vs. caster" battles, we were sure that was an issue, and spent a good 5 minutes trying to find where it said that.

I just declared "we're gonna say it does for now, and confirm later." Next session: "Nope, it doesn't provoke. So it won't from now on." Note that everyone was okay with switching back to the book rules.

Note that you can ready an action to attack someone if they start casting a spell - but that doesn't actually prevent the spell from being cast.

[TopCheese]

No one was really freaking out... we are comming from 3.5 and are doing a fairly by the book game so we can get used tl the differences. This is why i asked :p

I typed that wrong, I meant to convey that this isn't something you should be alarmed at or worry about until you talk with the DM over it.

So many people on this forum have a DM versus PC mentality and push for the overdramatic reaction to things like this.

[snacksmoto]

I just declared "we're gonna say it does for now, and confirm later." Next session: "Nope, it doesn't provoke. So it won't from now on."

I've always found this method to be the best. Research the rule changes between sessions if a quick search doesn't turn up any answers. Don't let rules lawyering spoil the fun.
If desired, a bit of retcon can be introduced to reverse the effects. "The zombie from last session clawed at you but actually missed." Start the session with the mage retcon healed of the damage the zombie incurred. The cleric who cast Cure Wounds on the mage afterwards retcon gets that spell slot returned.