Suppose I was playing a wizard. I say to my DM, "I ready my Magic Missile. I cast it when I take damage, at the attacker."
When the time comes, do I need to make a Constitution saving throw immediately before I cast to avoid losing concentration?
concentrationdnd-5ereadied-actionspells
Suppose I was playing a wizard. I say to my DM, "I ready my Magic Missile. I cast it when I take damage, at the attacker."
When the time comes, do I need to make a Constitution saving throw immediately before I cast to avoid losing concentration?
Best Answer
Yes, you do
The Readied action doesn't trigger until after your trigger completes:
When you ready a spell, you are concentrating on that spell as you hold it (PHB, 193)
Since your trigger is when I take damage and you are concentrating, you will have to make a concentration save per the rules on concentration:
If you fail, then you've lost your spell
Just to close the loop, if you do fail that concentration save, then you drop the readied spell and you won't be casting it.