Curious Giant Snail

Vigilance
{t}: Tap target vehicle and put a stun counter
on it. ("If a permanent with a stun counter on it
would become untapped, instead remove a stun
counter from it")
"Sir, ahem, i'm afraid to tell you, but, ehmmm,
the boat won't be leaving anytime soon.
We, umm, we have a ... giant snail situation."
-Klaas, doomed snailor