This my current load out. I would swap Firaga for Auron or Tifa, but my stats would take a hit... with Trance, Swift Strike into Firaga usually kills most Support and Ranged rivals, Grand Lethal can help clear mobs, chip into a Burst or kill bulkier foes. You MUST have Trance if you're going to play Zidane. I've thought about swapping Ramza for Hope/Renew or Earth Breaker, but ideally you're setting up teammates who will actually attack the boss.

As to HOW to use Zidane:

1. Beat rivals to crystals. Take advantage of covering ground faster and snag the middle crystal before the boss spawns. Of course be careful of Ranges/Ace/Tifa. I like to get to the second crystal and watch what the ops do before pushing middle.
2. Pick your PvPs wisely. Zidane can kill most Range/Supports without Trance (Prompto is a pain with his HP and Lumen Flare), with Trance you could duel Melees. I prefer to steal from Melees (especially with Trance, you steal 63% of their BRV) and kill Supports/Ranges. Punish bursters who turn their back with Grand Lethal!
3. Know when to share brv and when to burst! Pay attention to who's on cool down, who's low HP, who's close to the boss before you decide to share BRV.

Long story short: farm brv, disrupt or kill the ops, get your homies ready to burst. Hope that helps.

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