Forest Terrain

Green creatures get +1/+2.
Whenever you tap a creature for mana, add an additional mana of any colour to your mana pool.
At the beginning of your upkeep, you may put a creature card from your hand onto the battlefield with mana value equal or less to the number off lands you control.
Whenver a creature enters the battlefield under your control, you may put a land from your hand onto the battlefield.