User blog comment:SpookyBoogie27/Light Novel Spoilers/@comment-162.202.198.72-20130912060458/@comment-16281343-20130912131057

What wasn’t in the plan is Ophis joining. When the editor and I saw the volume 5 illustration of Ophis drawn by Miyama-san we fell in love with her and thought “Let’s make her join the group”. I didn’t originally have Ophis to be the last boss anyway so I made her remain as a mascot. So she will be active as mascot from now on as well.

-- vol. 12, Afterword.

~ So yeah, she will always be the mascot whether she regains her power or not.