Deep One Assault is a Loyal card - well known (and loathed by those it targets!) by almost every CoC player, I am sure.
I don't really think I need to explain what it does, since it's in the Core Set and one of the most popular Cthulhu cards in the game. Basically, what happens if I want to target a "Servant Out of Time" with it ?
The Servant is a 0-Cost character.... the DOA needs me to pay "X" where "X" is the cost of the targeted character. Since the character in this case costs "0" - in theory you should just be able to toss the DOA down "for free" and destroy him. Does the fact (in this case) that the DOA is "Loyal" - mean anything ? I did not think so (why would it ?) - and neither did my opponent, but just to be clear - we figured we'd ask here.
(this would apply beyond DOA to any Loyal card that somehow ended up "costing" 0, of course)