While you control a monster in your center Main Monster Zone, your opponent's monsters cannot attack, except to attack that monster. You can send 1 monster from your hand or field to the GY, then target 1 "Elfnote" monster in your GY with a different original Attribute; Special Summon it, then if you control a Synchro Monster, you can negate the effects of 1 face-up card your opponent controls until the end of this turn. You can only use this effect of "Elfnotes: Rhapsodia of Madness" once per turn.