Pantlaza, Sun-Forsaken

Whenever Pantlaza, Sun-Favored or another
Dinosaur enters the battlefield under your
control, you may Discover X, where X is that
creature's toughness. Do this only once each
turn.
(Discover — Exile cards from the top of your library
until you exile a nonland card with that mana
value or less. Cast it without paying its mana cost
or put it into your hand. Put the rest on the bottom
of your library in a random order.)