Last March of the Ents

This spell can't be countered.
Draw cards equal to the greatest toughness among creatures you control, then put any number of creature cards from your hand onto the battlefield.

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

Curious Altisaur

Vigilance, reach
Whenever a Dinosaur you control deals combat damage to a player, draw a card.

Intrepid Paleontologist

{T}: Add one mana of any color.
{2}: Exile target card from a graveyard.
You may cast Dinosaur creature spells from among cards you own exiled with Intrepid Paleontologist. If you cast a spell this way, that creature enters with a finality counter on it. (If a creature with a finality counter on it would die, exile it instead.)

Rhythm of the Wild

Creature spells you control can't be countered.
Nontoken creatures you control have riot. (They enter with your choice of a +1/+1 counter or haste.)

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Domri, Anarch of Bolas

Creatures you control get +1/+0.
+1: Add {R} or {G}. Creature spells you cast this turn can't be countered.
−2: Target creature you control fights target creature you don't control.

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

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.

Earthshaker Dreadmaw

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

Pantlaza, Sun-Favored

Whenever Pantlaza, Sun-Favored or another Dinosaur you control enters, 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.)

Kogla and Yidaro

When Kogla and Yidaro enters, choose one —
• It gains trample and haste until end of turn.
• It fights target creature you don't control.
{2}{R}{G}, Discard Kogla and Yidaro: Destroy up to one target artifact or enchantment. Shuffle Kogla and Yidaro into your library from your graveyard, then draw a card.

Rampaging Brontodon

Trample
Whenever Rampaging Brontodon attacks, it gets +1/+1 until end of turn for each land you control.

Ghalta and Mavren

Trample
Whenever you attack, choose one —
• Create a tapped and attacking X/X green Dinosaur creature token with trample, where X is the greatest power among other attacking creatures.
• Create X 1/1 white Vampire creature tokens with lifelink, where X is the number of other attacking creatures.

Kodama's Reach

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Herald's Horn

As Herald's Horn enters, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Broken Bond

Destroy target artifact or enchantment. You may put a land card from your hand onto the battlefield.

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.

Zacama, Primal Calamity

Vigilance, reach, trample
When Zacama, Primal Calamity enters, 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.

Bronzebeak Foragers

When Bronzebeak Foragers enters, for each opponent, exile up to one target nonland permanent that player controls until Bronzebeak Foragers leaves the battlefield.
{X}{W}: Put target card with mana value X exiled with Bronzebeak Foragers into its owner's graveyard. You gain X life.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Sol Ring

Kenrith's Transformation

Enchant creature
When Kenrith's Transformation enters, draw a card.
Enchanted creature loses all abilities and is a green Elk creature with base power and toughness 3/3. (It loses all other card types and creature types.)

Thunderherd Migration

As an additional cost to cast this spell, reveal a Dinosaur card from your hand or pay {1}.
Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Trumpeting Carnosaur

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

Forest

Contest of Claws

Target creature you control deals damage equal to its power to another target creature. If excess damage was dealt this way, discover X, where X is that excess damage. (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.)

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.

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.

Mountain

Garruk's Uprising

When this enchantment enters, if you control a creature with power 4 or greater, draw a card.
Creatures you control have trample. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)
Whenever a creature you control with power 4 or greater enters, draw a card.