As a reaction when you take damage, you can spend 1 or more ki points to reduce the damage by 10, plus an additional 5 damage per ki point spent. The next time you hit a creature with a melee weapon attack before the end of your next turn, you gain a bonus to the damage roll equal to half the damage blocked. You can't use this reaction again until you have released the energy in this way.

Holding so much energy can be perilous. If you're unable to release the energy before the end of your next turn, or if you become incapacitated while you're holding it, you take the damage instead.