Modern, Druid (20)
When Awakener Druid enters, target Forest becomes a 4/5 green Treefolk creature for as long as Awakener Druid remains on the battlefield. It's still a land.
Bear Form — During your turn, Circle of the Moon Druid is a Bear with base power and toughness 4/2. (It loses all other creature types.)
: Add .
Put a -1/-1 counter on Devoted Druid: Untap Devoted Druid.
Whenever you cast an Aura spell that targets Druid of Horns, create a 3/3 green Beast creature token.
As long as you control a token, Druid of the Spade gets +2/+0 and has trample.
Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Druid's Familiar is paired with another creature, each of those creatures gets +2/+2.
Whenever a creature you control attacks, put a charge counter on Druids' Repository.
Remove a charge counter from Druids' Repository: Add one mana of any color.
Ferocious — : Add . Activate only if you control a creature with power 4 or greater.
Eternalize (, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Snake Druid with no mana cost. Eternalize only as a sorcery.)
Whenever you cast a Druid spell, you may draw a card.
Tap seven untapped Druids you control: Gain control of all lands target player controls.
Rally — Whenever Grovetender Druids or another Ally you control enters, you may pay . If you do, create a 1/1 green Plant creature token.
: Add one mana of any type that a land you control could produce. If Incubation Druid has a +1/+1 counter on it, add three mana of that type instead.
: Adapt 3. (If this creature has no +1/+1 counters on it, put three +1/+1 counters on it.)
Kicker (You may pay an additional as you cast this spell.)
When Krosan Druid enters, if it was kicked, you gain 10 life.
, , Discard a card: Create a 1/1 green Elf Druid creature token named Llanowar Elves. It has ": Add ."
When you cast this spell, copy it if you control a planeswalker, Cleric, Druid, Shaman, Warlock, or Wizard.
Scry 1, then draw a card.
When Pollenbright Druid enters, choose one —
• Put a +1/+1 counter on target creature.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)
When Primal Druid dies, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Whenever you cast a spell that's white, blue, black, or red, put a +1/+1 counter on Questing Druid.
Exile the top two cards of your library. Until your next end step, you may play those cards.
When Sunshower Druid enters, put a +1/+1 counter on target creature and you gain 1 life.
Whenever you tap Zhur-Taa Druid for mana, it deals 1 damage to each opponent.
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