Deepwater Lurker

Ambush- When a creature with power equal to or less than this creatures power enters the battlefield under an opponents control, you gain 5 life and that creatures controller is dealt 5 damage. Damage dealt in this way can't be prevented or reduced.
When this creature ambushes a artifact creature, tap four lands that creatures controller owns.
Once the breach opened, many research vessels started disappearing, and many of the recovery vessels...