This is a little...silly, I think.
I can play one of these every time it wears off in a dedicated water deck...and it doesn't prevent you from playing instant or permanent spells so I can just mop you up with a Fire Bolt/Siphon Life or weapon.
Good luck trying to build up
for an Ice Bolt. This card consumes all
.
And the most damaging weapon is 8 damage... For 18 turns... That's 144 damage... OK, that's a bit too much.
I'm changing this to 2 turns.