War Caster 5e: Keep Your Concentration in Melee

What does War Caster do?

War Caster is built for spellcasters who end up in sword range. In the 2024 Player's Handbook it is a General feat for level 4 and up, and you need the Spellcasting or Pact Magic feature. It gives four benefits:

• Ability Score Increase: +1 Intelligence, Wisdom or Charisma, to a maximum of 20.
• Concentration: advantage on Constitution saving throws you make to keep concentration.
• Reactive Spell: when a creature provokes an opportunity attack by leaving your reach, you can use your reaction to cast a spell at it instead of swinging. The spell must take one action to cast and target only that creature.
• Somatic Components: you can make the hand gestures for spells while holding weapons or a shield in one or both hands.

What is the difference between 2014 and 2024 War Caster?

The rules text barely moved. The real upgrade is the +1 to your casting ability, which makes War Caster a half-feat: take it with a 17 in Wisdom or Charisma and you round up to 18. One side effect of the new prerequisite is that a character whose only spells came from a feat like Magic Initiate no longer qualifies, since that is not a Spellcasting feature.

How much does War Caster help concentration?

When you take damage while concentrating, you make a Constitution save against DC 10 or half the damage, whichever is higher (the 2024 rules cap it at DC 30). Most hits are under 22 damage, so DC 10 is the save you make most often. Here is your chance to keep the spell, worked out per d20 roll:

A cleric with +2 Constitution goes from losing concentration about 1 time in 3 at DC 10 to about 1 time in 8. Over a fight where you take three hits, the chance of keeping Spirit Guardians up through all of them rises from about 27% to about 68%. Those odds come from cubing the per-save chance, and they are the reason War Caster is a staple pick for clerics.

War Caster vs Resilient (Constitution)

Resilient gives proficiency in Constitution saves instead. At level 5 that turns +2 into +5: 80% at DC 10 and 55% at DC 15. War Caster on the same +2 gives 87.75% and 64%, so War Caster wins at level 5. Resilient catches up as your proficiency bonus grows, and it also covers poison and other Constitution saves. Classes that are already proficient in Constitution saves (sorcerers, and fighters such as the Eldritch Knight) get even more from War Caster's advantage, since it stacks on top.

Which spells can you cast with War Caster's Reactive Spell?

Any spell that takes one action and targets only the fleeing creature. A cantrip is usually best, because you keep your spell slots and the damage often beats a weak weapon swing.

• Eldritch Blast: the classic warlock pick. At level 5 you fire two beams, and both can hit the target.
• Shocking Grasp: a melee spell attack that also stops the target from making opportunity attacks.
• Inflict Wounds: a big burst of damage if you can spare a slot.
• Hold Person: cast at its base level it targets one humanoid and can stop the escape outright, though it costs a slot and your concentration.

Area spells like Fireball don't qualify, because they don't target a single creature.

Is War Caster worth it in 2024?

For any caster who stands in melee and concentrates, yes, it is often the first feat to take. That covers clerics with Spirit Guardians or Spiritual Weapon (both concentration in 2024), paladins holding Bless, sword-and-shield bladesingers, and Pact of the Blade warlocks. The somatic clause also saves sword-and-board characters from juggling their hands.

For a wizard or sorcerer who stays at the back and rarely gets hit, the Ability Score Improvement or Resilient is usually better. And if your concentration spells are short, like a 1-minute buff in short fights, you'll feel the benefit less.

Quick pick guide

• Cleric, paladin, melee druid: take War Caster at level 4 if your Wisdom or Charisma is odd.
• Bladesinger or Pact of the Blade warlock: War Caster for the reaction spell and full hands.
• Back-line wizard: Ability Score Improvement first, then Resilient (Constitution) later.
• Tanks who also cast: pair it with Sentinel so enemies pay for walking away.

FAQ

Is War Caster or Resilient (Constitution) better?

War Caster is better against low DCs, which is most concentration checks (DC 10 from any hit under 22 damage). Resilient adds your proficiency bonus, so it overtakes War Caster against high DCs and at high levels, and it helps against every Constitution save, not just concentration.

Can you cast Eldritch Blast with War Caster?

Yes. Eldritch Blast has a casting time of one action and can target only the fleeing creature, so it is a legal War Caster opportunity attack. Send every beam at that one target.

Does War Caster let you cast with a shield?

It lets you perform somatic components while holding weapons or a shield in one or both hands. Material components still need a hand free unless you use a focus that is part of your shield, like a cleric's holy symbol.

What changed with War Caster in 2024?

The three benefits are the same as 2014, but the 2024 feat now requires level 4 and adds +1 to Intelligence, Wisdom or Charisma, making it a half-feat.

Related

• Roll a d20
• Concentration in 5e Explained
• Sentinel Feat 5e: Lock Down Enemies (2024 Rules)
• Spirit Guardians 5e