Madness

Madness is an ability that allows you to pay an alternate cost for a spell when that spell is discarded. It was first induced in Odyssey block in Torment.

Madness also inspired an entire deck to be built around it. Using Wild Mongrel as a discard engine, one can discard and play their madness spells at any time as well as discard cards with flashback and the card Wonder, which makes all of your creatures fly.