Tribute to the World Tree

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

Ouroboroid

At the beginning of combat on your turn, put X +1/+1 counters on each creature you control, where X is this creature's power.

Magmatic Insight

As an additional cost to cast this spell, discard a land card.
Draw two cards.

Faeburrow Elder

Vigilance
This creature gets +1/+1 for each color among permanents you control.
{T}: For each color among permanents you control, add one mana of that color.

Rootless Yew

When this creature dies, search your library for a creature card with power or toughness 6 or greater, reveal it, put it into your hand, then shuffle.

Vengeful Regrowth

Return up to three target land cards from your graveyard to the battlefield tapped. Create that many 4/2 green Plant Warrior creature tokens with reach.
Flashback {6}{G}{G} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Jaddi Offshoot

Defender
Landfall — Whenever a land you control enters, you gain 1 life.

Rumbleweed

This spell costs {1} less to cast for each land card in your graveyard.
Vigilance, reach, trample
When this creature enters, other creatures you control get +3/+3 and gain trample until end of turn.

Ancient Greenwarden

Reach (This creature can block creatures with flying.)
You may play lands from your graveyard.
If a land entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Phylath, World Sculptor

When Phylath enters, create a 0/1 green Plant creature token for each basic land you control.
Landfall — Whenever a land you control enters, put four +1/+1 counters on target Plant you control.

Phytohydra

If damage would be dealt to this creature, put that many +1/+1 counters on it instead.

Decimate

Destroy target artifact, target creature, target enchantment, and target land. (You can't cast this spell unless you have legal choices for all its targets.)

Dune Chanter

Reach
Lands you control and land cards you own that aren't on the battlefield are Deserts in addition to their other types.
Lands you control have "{T}: Add one mana of any color."
{T}: Mill two cards. You gain 1 life for each land card milled this way.

Cactusfolk Sureshot

Reach
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
At the beginning of combat on your turn, other creatures you control with power 4 or greater gain trample and haste until end of turn.

Conduit of Worlds

You may play lands from your graveyard.
{T}: Choose target nonland permanent card in your graveyard. If you haven't cast a spell this turn, you may cast that card. If you do, you can't cast additional spells this turn. Activate only as a sorcery.