well of wisdom

Pay half your life and sacrifice half of
the permanents you control rounded up, {t}:
Search each opponent's hand and/or library. For
each opponent, you may exile one card from
his/her library or hand. You may look at and cast
cards exiled this way for as long as they remain in exile, and you may spend mana as though it
were mana of any type to cast that spell. If a
library is searched this way shuffle it.
Odin had sacrificed his eye to acquire this knowledge
-Mimir