Carnage Tyrant

This spell can't be countered.
Trample, hexproof

Snapping Sailback

Flash
Enrage — Whenever Snapping Sailback is dealt damage, put a +1/+1 counter on it. (It must survive the damage to get the counter.)

Dinosaur

Cresting Mosasaurus

Emerge {6}{U} (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.)
When Cresting Mosasaurus enters, if you cast it, return each non-Dinosaur creature to its owner's hand.

Star of Extinction

Destroy target land. Star of Extinction deals 20 damage to each creature and each planeswalker.

Scion of Calamity

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Whenever Scion of Calamity deals combat damage to a player, destroy target artifact or enchantment that player controls.

Thrasta, Tempest's Roar

This spell costs {3} less to cast for each other spell cast this turn.
Trample, haste
Trample over planeswalkers (This creature can deal excess combat damage to the controller of the planeswalker it's attacking.)
Thrasta, Tempest's Roar has hexproof as long as it entered this turn.

Rampaging Ferocidon

Menace
Players can't gain life.
Whenever another creature enters, Rampaging Ferocidon deals 1 damage to that creature's controller.

Rampaging Ceratops

Rampaging Ceratops can't be blocked except by three or more creatures.

Regisaur Alpha

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

Kinjalli's Sunwing

Flying
Creatures your opponents control enter tapped.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Compy Swarm

At the beginning of your end step, if a creature died this turn, create a tapped token that's a copy of Compy Swarm.

Ripscale Predator

Menace (This creature can't be blocked except by two or more creatures.)

Polyraptor

Enrage — Whenever Polyraptor is dealt damage, create a token that's a copy of Polyraptor.

Gigantosaurus

Overgrown Armasaur

Enrage — Whenever Overgrown Armasaur is dealt damage, create a 1/1 green Saproling creature token.

Scytheclaw Raptor

Whenever a player casts a spell, if it's not their turn, Scytheclaw Raptor deals 4 damage to them.

Silverclad Ferocidons

Enrage — Whenever Silverclad Ferocidons is dealt damage, each opponent sacrifices a permanent of their choice.

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.

Dinosaurs on a Spaceship

Vigilance, trample
Other Dinosaurs you control get +1/+1 and have vigilance and trample.
Suspend 4—{3}{R}{W}
Whenever a time counter is removed from Dinosaurs on a Spaceship while it's exiled, create a 2/2 red and white Dinosaur creature token with flying and haste.

Ornery Dilophosaur

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Whenever Ornery Dilophosaur attacks, if you control a creature with power 4 or greater, Ornery Dilophosaur gets +2/+2 until end of turn.

Raptor Hatchling

Enrage — Whenever Raptor Hatchling is dealt damage, create a 3/3 green Dinosaur creature token with trample.

Unnatural Growth

At the beginning of each combat, double the power and toughness of each creature you control until end of turn.

Wakening Sun's Avatar

When Wakening Sun's Avatar enters, if you cast it from your hand, destroy all non-Dinosaur creatures.

Zetalpa, Primal Dawn

Flying, double strike, vigilance, trample, indestructible

Collective Blessing

Charging Tuskodon

Trample
If Charging Tuskodon would deal combat damage to a player, it deals double that damage to that player instead.

Thrash of Raptors

As long as you control another Dinosaur, Thrash of Raptors gets +2/+0 and has trample.

Sun-Crowned Hunters

Enrage — Whenever Sun-Crowned Hunters is dealt damage, it deals 3 damage to target opponent or planeswalker.

Siegehorn Ceratops

Enrage — Whenever Siegehorn Ceratops is dealt damage, put two +1/+1 counters on it. (It must survive the damage to get the counters.)

Goring Ceratops

Double strike
Whenever Goring Ceratops attacks, other creatures you control gain double strike until end of turn.

Temple Altisaur

If a source would deal damage to another Dinosaur you control, prevent all but 1 of that damage.

Nezahal, Primal Tide

This spell can't be countered.
You have no maximum hand size.
Whenever an opponent casts a noncreature spell, draw a card.
Discard three cards: Exile Nezahal, Primal Tide. Return it to the battlefield tapped under its owner's control at the beginning of the next end step.

The Tarrasque

The Tarrasque has haste and ward {10} as long as it was cast.
Whenever The Tarrasque attacks, it fights target creature defending player controls.

Raging Swordtooth

Trample
When Raging Swordtooth enters, it deals 1 damage to each other creature.

Ruinous Ultimatum

Destroy all nonland permanents your opponents control.

Roar of the Fifth People

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after IV.)
I — Create two 3/3 green Dinosaur creature tokens.
II — Roar of the Fifth People gains "Creatures you control have '{T}: Add {R}, {G}, or {W}.'"
III — Search your library for a Dinosaur card, reveal it, put it into your hand, then shuffle.
IV — Dinosaurs you control gain double strike and trample until end of turn.

Huatli, Poet of Unity

When Huatli, Poet of Unity enters, search your library for a basic land card, reveal it, put it into your hand, then shuffle.
{3}{R/W}{R/W}: Exile Huatli, then return her to the battlefield transformed under her owner's control. Activate only as a sorcery.

Huatli, Poet of Unity // Roar of the Fifth People

Tetzimoc, Primal Death

Deathtouch
{B}, Reveal Tetzimoc, Primal Death from your hand: Put a prey counter on target creature. Activate only during your turn.
When Tetzimoc enters, destroy each creature your opponents control with a prey counter on it.

Etali, Primal Storm

Whenever Etali attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Ghalta, Primal Hunger

This spell costs {X} less to cast, where X is the total power of creatures you control.
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Frilled Deathspitter

Enrage — Whenever Frilled Deathspitter is dealt damage, it deals 2 damage to target opponent or planeswalker.

The Skullspore Nexus

This spell costs {X} less to cast, where X is the greatest power among creatures you control.
Whenever one or more nontoken creatures you control die, create a green Fungus Dinosaur creature token with base power and toughness each equal to the total power of those creatures.
{2}, {T}: Double target creature's power until end of turn.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")