So unless you have some self-discard synergy of your own, he would almost become unplayable after a certain point
Magic: The Gathering Website
Spot protection cards are only sometimes helpful, although powerful defensive effects like Teferi's Protection and Hero's Intervention can shut down an opponent who was counting on their Exile spells paying off.
Limited Edition , Arabian Nights , Antiquities , and Legends all contained a few cards that were considered problematic to competitive play, and many had to be restricted at one point or another
Because playtest cards are a mixed bag, this ranking may be even more subjective than normal
Just like those former rarity introductions, however, this one seems to be losing its luster