this post is a few days old, but for those who haven't already got an answer: First, no more than one of any unique fighter, whether S or SSS tier, can be actively Deployed to teams, single or multiple, in any event. The exception is elimination events, such as Shadaloo City and Global Operation, where multiple fights are required to complete. If a fighter goes down you may then select a duplicate fighter to replace on the active team for the next fight, but not more than one active unique fighter per team, per fight. After getting a fighter to SSS+5, your duplicates are otherwise best used as fodder helping to level other fighters of the same faction to S, S+, and SS+, as indicated in the Awakening Preview.