Fyres, Frozen Monarch

When Fyres, Frozen Monarch enters the battlefield, put a Glacier counter on target land.
Lands with Glacier counters on them become a snow land named Glacier and have {t}: Add {w} or {u}
{s}{s}{s}: Put a Glacier counter on target land or remove a Glacier counter from target land.
"Like the cold, my reign is unavoidable."