Restless Ridgeline

Restless Ridgeline enters tapped.
{T}: Add {R} or {G}.
{2}{R}{G}: Restless Ridgeline becomes a 3/4 red and green Dinosaur creature until end of turn. It's still a land.
Whenever Restless Ridgeline attacks, another target attacking creature gets +2/+0 until end of turn. Untap that creature.

Forest

Trumpeting Carnosaur

Trample
When Trumpeting Carnosaur enters, discover 5.
{2}{R}, Discard Trumpeting Carnosaur: It deals 3 damage to target creature or planeswalker.

Mountain

Commune with Dinosaurs

Look at the top five cards of your library. You may reveal a Dinosaur or land card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Kinjalli's Caller

Dinosaur spells you cast cost {1} less to cast.

Boseiju, Who Endures

{T}: Add {G}.
Channel — {1}{G}, Discard Boseiju, Who Endures: Destroy target artifact, enchantment, or nonbasic land an opponent controls. That player may search their library for a land card with a basic land type, put it onto the battlefield, then shuffle. This ability costs {1} less to activate for each legendary creature you control.

Topiary Stomper

Vigilance (Attacking doesn't cause this creature to tap.)
When Topiary Stomper enters, search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Topiary Stomper can't attack or block unless you control seven or more lands.

Belligerent Yearling

Trample
Whenever another Dinosaur you control enters, you may have Belligerent Yearling's base power become equal to that creature's power until end of turn.

Thrashing Brontodon

{1}, Sacrifice this creature: Destroy target artifact or enchantment.

Karplusan Forest

{T}: Add {C}.
{T}: Add {R} or {G}. Karplusan Forest deals 1 damage to you.

Eiganjo, Seat of the Empire

{T}: Add {W}.
Channel — {2}{W}, Discard Eiganjo, Seat of the Empire: It deals 4 damage to target attacking or blocking creature. This ability costs {1} less to activate for each legendary creature you control.

Tranquil Frillback

When Tranquil Frillback enters, you may pay {G} up to three times. When you pay this cost one or more times, choose up to that many —
• Destroy target artifact or enchantment.
• Exile target player's graveyard.
• You gain 4 life.

Pugnacious Hammerskull

Whenever Pugnacious Hammerskull attacks while you don't control another Dinosaur, put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Etali, Primal Sickness

Trample, indestructible
Whenever Etali, Primal Sickness deals combat damage to a player, they get that many poison counters. (A player with ten or more poison counters loses the game.)

Etali, Primal Conqueror

Trample
When Etali, Primal Conqueror enters, each player exiles cards from the top of their library until they exile a nonland card. You may cast any number of spells from among the nonland cards exiled this way without paying their mana costs.
{9}{G/P}: Transform Etali. Activate only as a sorcery.

Etali, Primal Conqueror // Etali, Primal Sickness

Stomping Ground

({T}: Add {R} or {G}.)
As Stomping Ground enters, you may pay 2 life. If you don't, it enters tapped.

Battlefield Forge

{T}: Add {C}.
{T}: Add {R} or {W}. Battlefield Forge deals 1 damage to you.

Brushland

{T}: Add {C}.
{T}: Add {G} or {W}. Brushland deals 1 damage to you.

Sacred Foundry

({T}: Add {R} or {W}.)
As Sacred Foundry enters, you may pay 2 life. If you don't, it enters tapped.

Temple Garden

({T}: Add {G} or {W}.)
As Temple Garden enters, you may pay 2 life. If you don't, it enters tapped.

Itzquinth, Firstborn of Gishath

Haste
When Itzquinth, Firstborn of Gishath enters, you may pay {2}. When you do, target Dinosaur you control deals damage equal to its power to another target creature.

Ixalli's Lorekeeper

{T}: Add one mana of any color. Spend this mana only to cast a Dinosaur spell or activate an ability of a Dinosaur source.

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

Earthshaker Dreadmaw

Trample
When Earthshaker Dreadmaw enters, draw a card for each other Dinosaur you control.