Misty Rainforest

{T}, Pay 1 life, Sacrifice this land: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

Arbor Elf

Guardian Project

Whenever a nontoken creature you control enters, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

Elvish Mystic

Ezuri, Claw of Progress

Whenever a creature you control with power 2 or less enters, you get an experience counter.
At the beginning of combat on your turn, put X +1/+1 counters on another target creature you control, where X is the number of experience counters you have.

Command Tower

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

Forest

Breeding Pool

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

Fyndhorn Elves

Sage of Hours

Heroic — Whenever you cast a spell that targets this creature, put a +1/+1 counter on it.
Remove all +1/+1 counters from this creature: For each five counters removed this way, take an extra turn after this one.