Trugan Border Wurm

Defender, trample
Trugan Border Wurm's power and toughness are
equal to the number of lands you control.
Whenever a land enters the battlefield under your
control Trugan Border Wurm loses defender
until end of turn. If you control more lands than
each opponent Trugan Border Wurm's power
and toughness is also equal to the number of
lands on the battlefield until end of turn.