CHAOS SHIELD

You infuse the spells of those who dare attack you with the
randomness of pure chaos. The caster of the spell that triggers your
reaction must make a Constitution saving throw. On a failure, the
spell goes wild, and the caster must roll on the Chaos Surge table
to determine the effect. Additionally, the caster becomes glitched for
one minute. While glitched, each time the caster casts a spell using
a spell slot, there is a 50% chance the spell goes wild. An affected
caster can repeat its saving throw at the end of each of its turns,
ending the effect on a success.