Earth, Mercator Projection

When Earth, Mercator Projection comes
into play and its controller has already a
'Land - Projection'-card in play, return that
Land to its owner's hand.
{t}: Add {1} to your Mana Pool.
{3}{t}: Put a 1/1 Gaia Token into play.
Sacrifice an untapped Gaia Token: add {3} of any colour to your Mana Pool.
"Projection used for navigation."