Elvish Mystic

Tribute to the World Tree

Whenever a creature enters the battlefield under your control, draw a card if its power is 3 or greater. Otherwise, put two +1/+1 counters on it.

Selvala, Eager Trailblazer

Vigilance
Whenever you cast a creature spell, create a 1/1 red Mercenary creature token with "{T}: Target creature you control gets +1/+0 until end of turn. Activate only as a sorcery."
{T}: Choose a color. Add one mana of that color for each different power among creatures you control.

Plains

Leyline of Vitality

If Leyline of Vitality is in your opening hand, you may begin the game with it on the battlefield.
Creatures you control get +0/+1.
Whenever a creature enters the battlefield under your control, you may gain 1 life.

Sigil Captain

Whenever a creature enters the battlefield under your control, if that creature is 1/1, put two +1/+1 counters on it.

God-Eternal Oketra

Double strike
Whenever you cast a creature spell, create a 4/4 black Zombie Warrior creature token with vigilance.
When God-Eternal Oketra dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

Forest

Ronin Warclub

Equipped creature gets +2/+1.
Whenever a creature enters the battlefield under your control, attach Ronin Warclub to that creature.
Equip {5} ({5}: Attach to target creature you control. Equip only as a sorcery.)

Suture Priest

Whenever another creature enters the battlefield under your control, you may gain 1 life.
Whenever a creature enters the battlefield under an opponent's control, you may have that player lose 1 life.

Oltec Matterweaver

Whenever you cast a creature spell, choose one —
• Create a 1/1 colorless Gnome artifact creature token.
• Create a token that's a copy of target artifact token you control.

Ajani's Welcome

Whenever a creature enters the battlefield under your control, you gain 1 life.

Durable Handicraft

Whenever a creature enters the battlefield under your control, you may pay {1}. If you do, put a +1/+1 counter on that creature.
{5}{G}, Sacrifice Durable Handicraft: Put a +1/+1 counter on each creature you control.