Unkind Rewind

9th-level transmutation

Casting Time:1 reaction

Range:Self (150-foot diameter sphere)

Components:V, S, M (an hourglass filled with diamond dust, which the spell consumes)

Duration:Instantaneous

At the end of a round, you can choose to cast this spell, putting everything in range within a state of temporal flux. You then rewind time in that area by 6 seconds. Everything that happened in in that round is undone and the area and creatures revert back to the state they were at the beginning of the round. There is no saving throw against this spell.

Altering time in this way is almost always deadly to the caster. After the spell has finished, the caster is reduced to 0 hit points. The caster then has disadvantage on all saving throws, including death saving throws, until they finish a long rest. In addition, casting this spell doubles the rate at which the caster ages. This effect is cumulative, meaning that if a caster uses this spell 4 times, they would age at 16 times their normal rate.