NOTE: Keep in mind that you have to have the right requirements to enter his lair (see article Keep out signs for what they are).
He is the "boss" monster for several of the mini-games on Dizzywood (like Combo Drop). When you defeat him, you can choose one of his swamp furniture treasures as your reward and you can place it in your own home like all the henchmen do when they're defeated.
NOTE: This has to be done quickly as you cannot hang around Grool's Lair for long after winning.
History of Grool GrubnibblerEdit
Grool Grubnibbler was a sad and pathetic swamp monster before he was discovered by Emperor Withering. Withering saw the potential for great cruelty in Grool and immediately recruited him for his growing group of henchmen, The Underlings. Grool operates primarily out of The Noxious Swamp near Tanglevine Jungle.