Whenever Tyrannosaurus Rex attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.
Near Mint - $31.20
Lightly Played - $28.10
Played - $21.90
Heavily Played - $18.70
Damaged - $15.60
Near Mint Non-English - $31.20
Lightly Played Non-English - $28.10
Played Non-English - $21.90
Heavily Played Non-English - $18.70
Damaged Non-English - $15.60