Eayn, Kig-Yar Homeworld

({t}: Add {g}, {u}, or {r} to your mana pool.)
As Eayn, Kig-Yar Homeworld enters the battlefield, you may pay 3 life. If you don't, Eayn, Kig-Yar Homeworld enters the battlefield tapped.
The world's surface is characterized by a single large ocean, sparse volcanic activity and the vegetation is similar to that seen in tropical rain forests on Earth.