Grand Magus appears in the Adamah Block of Tartarus, from floors 229 to 235. In this block, it will also be accompanied by a Vehement Idol. These shadows will also appear in the Monad Depths in groups and will be mixed with other shadow types from the 6th floor onward.
Grand Magus appears on Paths 3 and 4 of Yomotsu Hirasaka within the Midnight Channel. It will alternate between attacking with its Fire and Electricity spells. After being defeated, it may drop a piece of Living Metal. Selling 10 Living Metal at the TV extension of Daidara will unlock the Life Fob accessory.
In Golden, Grand Magus attacks with low level AOE versions of all elemental spells. It will also use Mind Charge to amplify its Megidola.