Special Ability Submissions Thread

My idea is very similar to the one of Egger

She would "Fuse" with an esper. I guess it could be with the equipped one, or within a list of 6-8. The esper could appear behind her, like with sketch. Thereafter, a second battle menu appear, like with "control", and she use ability related to the esper, not necessarily the spells she gives. Like Gau, she would gain status ailment and elemental resistances of the esper. Part of her pallette could change depending on the esper with a custom status ailment.
With this, you have great versality and you will be able to discover new things with each esper.
Also, another possiblity is, we could make the ability a lot stronger, but make it that a magicite is required to use the ability

Also, are we discussing about a relic that change the ability? Like fakemustache?
If so, i suggest that the relic change "Fuse" for "Wild Magic", which cast a random magic black magic, but alot stronger than the normal version. It could also rarely cast esper attack.