Real Double

is a Mirror Magic spell.

Description
The users would open their grimoire in order to activate the spell. Once activated, a mirror would manifest in front of the user as the tool to use the spell. The users are then able to create a clone of themselves, which has inverted outer features. It is because the said clone is the mirrored version of the users.

The clone then could assist the users in a fight, because it is capable of using the same spells in which used by the users. Thus, the users are able to launch an enhanced attack, which has twice the power of the original attack.