Accelgor

As an additional cost to cast Accelgor, sacrifice
Shelmet.
When Accelgor deals combat damage to target opponent or Planeswalker, tap a land that
opponent controls. That land doesn't untap
during its controller's next untap step.
{g}{g}: Accelgor gets +3/+0 until end of turn.
Having removed its heavy shell, it becomes very light
and can fight with ninja-like movements.