Oldie but a Goodie

When this creature enters, sacrifice it unless you return three basic lands you control to their owner's hand. , Return this creature to its owner's hand: Destroy target creature. It can't be regenerated. That creature's controller creates a 0/1 green Sheep creature token.

You may play any number of lands on each of your turns. Whenever you play a land, if it wasn't the first land you played this turn, this enchantment deals 1 damage to you.

Sacrifice a land: You gain 2 life.

You may play lands from your graveyard.

Creatures you control get +3/+3 and gain trample until end of turn. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)

Any player may cast creature spells with mana value 3 or less without paying their mana costs and as though they had flash.