Anti-counterspell, anti-milling... anti-Blue :)

EDIT: also anti-discard which is kinda anti-Black.

Also anti-black for its Guerrilla Tactics impression.

May need "by a spell or ability an opponent controls", otherwise Wild Mongrels and Traumatizes go completely crazy.

I like this; it's mainly a nice little "Aww, I didn't get to use my cheap powerful creature, at least it burns you slightly on the way out"

But yes, sadly, probably needs the extra words; or it becomes "And now all of my discard-powered goodstuff is even better". Which leads to madness. (Heh.)

Although gosh; it tempts me to suggest it as a win condition for the Wheel of Fortune deck.

I kinda like the "you can do it to yourself" side of things.

Though it makes Red looting rather good.

Maybe add a cost for the madness then? seems like a sensible cost for a lightning bolt?

Although it's kinda more red for it to be as it is now - a non optional three damage that has to go somewhere. Sadly, it'll be an incredibly rare, rather than just memorably rare, occasion where it has to hit yourself.

Huh. Well, I'd say that this card is better than Fiery Temper for two reasons (easier to trigger 'Madness' and casting the spell gives you a different result. Oh, also, you can deal damage, then recur this as a creature, so I guess that's a third reason.)

That said, I don't know whether Fiery Temper is good enough by today's standards. It was certainly stellar in Torment. Timeshifted rating is 4.009... I suppose that's for a reason...