Legacy Demonic Mouboo
From TMW: rEvolt
May mutate 1 attribute up to 30%.
Demonic Mouboos are aggressive creatures found while doing the Orum and Waric follow-up quest. They come from the astral plane and only make it to The Mana World while helping Orum with his evil magic plans. However, they are weaker than usual Mouboos since their HP, resistance (DEF), and strength (ATK1-2) are lower, so if you are able to kill a Mouboo, a single demonic one won't make you problems.
If you are lucky you will get an Emerald after defeating a Demonic Mouboo. The chance for it is 0.5%.
The drops of a Demonic Mouboo can be used in the following quests: