Chair of Doom

Whenever Chair of Doom becomes saddled,
transform it into Chair of Doom's Little Secret.
When Chair of Doom's Little Secret transforms back, sacrifice the creature saddling it.

Chair of Doom's Little Secret is a 6/6 black horror creature with Haste and "at the end of this turn, transform Chair of Doom's Little Secret into Chair
of Doom".
Saddle 1
Madness—{b}{b}