The Robe of Magical Reaction
Wondrous item, unique, requires attunement
This robe grants the wearer advantage on Saving Throws vs. spells. If the wearer fails a Saving Throw vs. spell in spite of this, roll 2d4 on the following table:
2: The spell has no effect. The spell Antimagic Field is cast on you.
3: The spell takes effect as normal. Immediately afterward, Otiluke’s Resilient Sphere is cast on you.
4: The spell affects you as normal
5: Counterspell is cast on the spell. Roll as you normally would for spells higher than Level 3
6: The spell affects you as normal, and if you took damage of the following types: acid, cold, fire, lightning, or thunder damage, you fall under the effects of the spell Protection from Energy. This takes no spell concentration on your part.
7: The spell is absorbed by the robe, it has no effect. You gain a spell slot equal to the spell’s base level. It is lost when used.
8: The spell has no effect, and you fall under the effects of the spell Circle of Power. You must concentrate as normal to maintain this spell.