"Gren Maju Da Eiza"'s effect includes cards removed from play face-down with "Lightforce Sword" or "Different Dimension Capsule".
If you equip "Axe of Despair" to "Gren Maju Da Eiza", calculate its ATK and DEF according to its effect, then add +1000 ATK on top of that.
If "Gren Maju Da Eiza" is equipped with "Megamorph", its ATK is zero, but if "Megamorph" leaves play, recalculate its ATK using its effect.