Madness is a spell card.
How to Get
The following cards create tokens of Madness (or transform cards into it):
Alternatively, it can be used to remove a troublesome blocker, and then attack with it as well.
Cards you steal that die while under your control will go to your void. If the card is returned to play, it will remain under your control, even if it is returned on the same turn it is stolen.
If you have a full board when you steal a unit, the unit will go directly to your void.