Five mana to exile most non-land permanents is a lot of mana in an absolute sense, but it could be worthwhile if you are in a color that struggles to find hard removal
There will no doubt be new legendary creatures to compliment or even overhaul many decks, as well as spawn new ones
Combining Tivit, Seller of Secrets with Time Sieve, players will, therefore, be able to take infinite turns as long as they can do combat damage with Tivit or flicker it each turn
All you need to do from there to run away with the game is protect your Commander, which is exactly what Tyvar, the Pummeler and Underrealm Lich do from your graveyard
Ego Drain loses its downside when you control a fairy, while Nectar Faerie can give one of your faeries lifelink for a turn