Waterspout Sovereign

When attacking, Waterspout Sovereign's power
is equal to the number of Islands defending
player controls. Otherwise, its power is equal to
the number of Islands you control.
When Waterspout Sovereign enters the battlefield, create a 1/1 blue Elemental creature
token for each Island you control.
{u}, Sacrifice an Elemental: Target land becomes
an Island in addition to its other types.