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.
NM-Mint - $17.20
Lightly Played - $15.50
Moderately Played - $13.70
Heavily Played - $12.00
Damaged - $8.60
NM-Mint Non English - $17.20
Lightly Played Non English - $15.50
Moderately Played Non English - $13.70
Heavily Played Non English - $12.00
Damaged Non English - $8.60