Midnight Guard

Whenever another creature enters, untap Midnight Guard.

Ivy Lane Denizen

Whenever another green creature you control enters, put a +1/+1 counter on target creature.

Enchant creature
Enchanted creature has "{T}: Create a 1/1 green Elf Warrior creature token."

When Heliod's Pilgrim enters, you may search your library for an Aura card, reveal it, put it into your hand, then shuffle.

Counter target spell unless its controller pays {1}.

{T}: Add {G}.
Put a -1/-1 counter on Devoted Druid: Untap Devoted Druid.