Prophecy of Ruin

Starting at 14th level, you can spend 10 minutes talking to a crowd of people, recounting a vision foretold by your patron. Once the prophecy concludes, choose a number of creatures within 60 feet of you who listened to all of it (which can include yourself), up to a number equal to your Warlock level. A target is unaffected if it doesn't understand your language.

The first time a target is reduced to 0 hit points as a result of taking damage, it can use its reaction to take an action, before dying or falling unconscious.

This effect ends on a target once it finishes a long rest, after which time it can benefit from this feature again.