Graven Basin enters the battlefield tapped unless you sacrifice an artifact.
: Add or to your mana pool.
: Add to your mana pool. Put Graven Basin on top of your library.
, Sacrifice Graven Basin: Target creature gets +2/+2 until end of turn.
: Add 
or 
to your mana pool.: Add 
to your mana pool. Put Graven Basin on top of your library., Sacrifice Graven Basin: Target creature gets +2/+2 until end of turn.
