A Mega-Shadow has a vaguely humanoid body structure. It has a round, spherical head with circular, glowing yellow eyes. It also has two long, twisted antennae sprouting out of the top of its head. Each of its hands has three clawed fingers, and its feet are large and lack any discernible digits. With the exception of its eyes, this Heartless's body is completely pitch-black. The Mega-Shadow is identical to the basic Shadow and Gigas Shadow, and is between the two in size.
The Mega-Shadow’s name references its large size—"mega-" is a prefix meaning "large" or "great"—and its otherwise identical appearance to basic Shadows.
Mega-Shadows are larger variants of the Shadow, using similar attacks. They can sink into the ground to become invulnerable, but a well-timed magic attack may damage them before this occurs. Fire and Aero damage the Mega-Shadow effectively. While magic can be used to quickly eliminate a Mega-Shadow, physical attacks are what is mainly recommended to eliminate them.
They tend only to attack with a simple scratching tactic, which can be either avoided with Dodge Roll or protected against with Block. When a Mega-Shadow's attack is blocked with Block, it shall become stunned for several seconds and open to attacks. They may also perform a body slam; Dodge Roll a good way to avoid this. Mega-Shadows have little HP and can be easily eliminated, regardless of the player's current level.