Majin Buu's Sealed Ball

[Field] (Place and activate this card in the Battle Area. It remains in the Battle Area until you activate another [Field]. When you do, place this card in the Drop Area)
[Auto] [Once per turn] When the number of cards under this card reaches 5 or higher, place this card in the Drop Area, then choose up to 1 "Majin Buu Revived" from your deck and play it. Then, shuffle your deck.