When you cast this spell, Mirror Myr enters the battlefield with:

•A Plains counter on it if {W} was spent to cast it.

•An Island counter on it if {U} was spent to cast it.

•A Swamp counter on it if {B} was spent to cast it.

•A Mountain counter on it if {R} was spent to cast it.

•A Forest counter on it if {g} was spent to cast it.

If Mirror Myr has a counter on it, it is a Land in addition to its other types.