Gishath, Sun's Avatar

Vigilance, trample, haste
Whenever Gishath, Sun's Avatar deals combat damage to a player, reveal that many cards from the top of your library. Put any number of Dinosaur creature cards from among them onto the battlefield and the rest on the bottom of your library in a random order.

Ghalta, Primal Hunger

This spell costs {X} less to cast, where X is the total power of creatures you control.
Trample

Regisaur Alpha

Other Dinosaurs you control have haste.
When Regisaur Alpha enters the battlefield, create a 3/3 green Dinosaur creature token with trample.

Zacama, Primal Calamity

Vigilance, reach, trample
When Zacama, Primal Calamity enters the battlefield, if you cast it, untap all lands you control.
{2}{R}: Zacama deals 3 damage to target creature.
{2}{G}: Destroy target artifact or enchantment.
{2}{W}: You gain 3 life.

Zetalpa, Primal Dawn

Flying, double strike, vigilance, trample, indestructible

Return of the Wildspeaker

Choose one —
• Draw cards equal to the greatest power among non-Human creatures you control.
• Non-Human creatures you control get +3/+3 until end of turn.

Garruk's Uprising

When Garruk's Uprising enters the battlefield, if you control a creature with power 4 or greater, draw a card.
Creatures you control have trample. (They can deal excess combat damage to the player or planeswalker they're attacking.)
Whenever a creature with power 4 or greater enters the battlefield under your control, draw a card.