As Rukarumel, Biologist enters the battlefield, choose a creature type.

Slivers you control and nontoken creatures you control are the chosen type in addition to their other creature types. The same is true for creature spells you control and creature cards you own that aren’t on the battlefield.

{3}, {T}: Create a 1/1 colorless Sliver creature token.

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. (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.)