Hydra Broodmaster

{X}{X}{G}: Monstrosity X. (If this creature isn't monstrous, put X +1/+1 counters on it and it becomes monstrous.)
When this creature becomes monstrous, create X X/X green Hydra creature tokens.

Heroes' Bane

This creature enters with four +1/+1 counters on it.
{2}{G}{G}: Put X +1/+1 counters on this creature, where X is its power.

Forest

Strength from the Fallen

Constellation — Whenever this enchantment or another enchantment you control enters, target creature gets +X/+X until end of turn, where X is the number of creature cards in your graveyard.

Humbler of Mortals

Constellation — Whenever this creature or another enchantment you control enters, creatures you control gain trample until end of turn.

Ravenous Leucrocota

Vigilance
{6}{G}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)

Nessian Game Warden

When this creature enters, look at the top X cards of your library, where X is the number of Forests you control. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in any order.

Golden Hind

Oakheart Dryads

Constellation — Whenever this creature or another enchantment you control enters, target creature gets +1/+1 until end of turn.

Font of Fertility

{1}{G}, Sacrifice this enchantment: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.