Kelp Behemoth

Whenever Kelp Behemoth or another Plant
enters the battlefield under your control, tap
target creature. That creature doesn't untap
during its controller's next untap step.
Whenever Kelp Behemoth is dealt damage,
create a 0/1 blue Plant Wall creature token with defender.
When Kelp Behemoth dies, put a +1/+1 counter
on each plant you control.