I have an idea for a card that is something of a counter to over-used creatures like Otyugh and Scarab: Ouroboros would have the image of a snake consuming it's tail in a ring, and would cause a creature with devour to self-annihilate by eating itself, basically. If a card has another ability or none at all, it's replaced by devour.
I think it might fit into the theme of the Time element (Ourosboros also symbolizes infinity), but I wonder if the idea is too situational?
[/edit] Posted this in the wrong subforum...