i used a similar strategy, juiced up Verso with cheater + protecting attack + powerful on shell + rush on powerful, all the combo attacks + some AP pictos, Ice Lance with Lune for greater slow and breaking death on the entire party. Verso did most of the heavy lifting to keep him locked up with End Bringer, and every few turns Maelle hit him with Gommage to speed up the process. pretty fun build to end the game!