When you sleep in a double, a California King seems monstrous.... but, back to hijack-DMing the thread....
The bed itself fails to animate, but the satin sheets eat the rock in a manner that leaves nothing visible afterward of any foul play, save for a slightly sticky white stain.
The canopy silks lash out, entangling all within six feet, and the pillows flip upward, revealing glowing red eyes filled with lustful malevolence... or maybe malevolent lust...
The bearskin rug latches its teeth onto the nearest ankle (rolls die) and mud duck must make a fortitude save or lose his left foot...
If he makes his save, he has a really odd hickey to brag about, later.