Pantlaza, Sun-Favored

Whenever Pantlaza, Sun-Favored or another
Dinosaur you control enters, you may
discover X, where X is that creature’s
toughness. Do this only once each turn.
(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
in a random order.)