Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
When Dinosaur Egg dies, you may discover X, where X is its toughness.
The Oltec revere dinosaurs as living remnants of the bygone Fourth Age.
It's sort of like a "fixed" Cascade. You exile cards from the top of your deck until you reveal a card with mana value less than or equal to the Discover number, then you can cast it or put it in your hand