What is the reward for the concealed ruins in Mystery Dungeon 2?

at the end you fight raikou but you need secret slab/mystery part to recruit him and then there's six deluxe boxes at the end at the end you fight raikou but you need secret slab/mystery part to recruit him and then there's six deluxe boxes at the end ----- at floor 20 (30 floors) theres raikou need secret slab or mystery part (as said above). at floor 29 there is a key room containing a chest with the item for either regirock ice steel or regigigas (but sometimes theres a wonder gummi in it instead)