Jetmir's Garden

({T}: Add {R}, {G}, or {W}.)
This land enters tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Eladamri's Call

Search your library for a creature card, reveal that card, put it into your hand, then shuffle.

Wall of Omens

Defender
When this creature enters, draw a card.

Spirited Companion

Hamza, Guardian of Arashin

This spell costs {1} less to cast for each creature you control with a +1/+1 counter on it.
Creature spells you cast cost {1} less to cast for each creature you control with a +1/+1 counter on it.

Herd Baloth

Whenever one or more +1/+1 counters are put on this creature, you may create a 4/4 green Beast creature token.

Nightshade Peddler

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as this creature is paired with another creature, both creatures have deathtouch.

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.

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — This Saga gains "{T}: Add {C}."
II — This Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This token gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Rumor Gatherer

Alliance — Whenever another creature you control enters, scry 1. If this is the second time this ability has resolved this turn, draw a card instead.

Eternal Witness

When this creature enters, you may return target card from your graveyard to your hand.

Inspiring Overseer

Flying
When this creature enters, you gain 1 life and draw a card.

Ripjaw Raptor

Enrage — Whenever this creature is dealt damage, draw a card.

Elvish Visionary

Beast Within

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

Urban Daggertooth

Vigilance
Enrage — Whenever this creature is dealt damage, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Tocasia's Welcome

Whenever one or more creatures you control with mana value 3 or less enter, draw a card. This ability triggers only once each turn.

Wall of Blossoms

Basilisk Collar

Equipped creature has deathtouch and lifelink. (Any amount of damage it deals to a creature is enough to destroy it. Damage dealt by this creature also causes you to gain that much life.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Rite of Harmony

Whenever a creature or enchantment you control enters this turn, draw a card.
Flashback {2}{G}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Marath, Will of the Wild

Marath enters with a number of +1/+1 counters on it equal to the amount of mana spent to cast it.
{X}, Remove X +1/+1 counters from Marath: Choose one —
• Put X +1/+1 counters on target creature. X can't be 0.
• Marath deals X damage to any target. X can't be 0.
• Create an X/X green Elemental creature token. X can't be 0.

Generous Gift

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

Loran of the Third Path

Vigilance
When Loran enters, destroy up to one target artifact or enchantment.
{T}: You and target opponent each draw a card.

Bellowing Aegisaur

Enrage — Whenever this creature is dealt damage, put a +1/+1 counter on each other creature you control.