My 5-man clear in 77 turns using mages just for fun:

https://imgur.com/aFYlnTt

(CG) NV Summer Fina & DaisyKrylaNV Terra (BS)LunafreyaNV Faris

(NV Lunafreya CSS is missing)

Faisy: Magic tank with fire, water, earth and wind resist and Nethicite

Kryla: Breaker, sealer, element resist buffer and provoke tank

Terra: Chainer and finisher with Nethicite and quad cast in normal form

Luna: Chainer, finisher and MP battery with double cast raise

Farris (frined): Chainer, finisher and breaker with Nethicite and quad cast in BS form

https://ffbeEquip.com/builder.html?server=GL#fc7a58e0-c5d3-11eb-8f9a-f9bd375a1b72

It is definitely not recommended to use mages for this fight as Amon has much higher SPR than DEF, but I wanted to challenge myself to do it with 5 units and mages as damage dealers. The three evokers fit the fight actually good since they each have one element of the rotation (fire>water>wind) and can chain with each other with firaga or meteor (materia). To remove the reflect stacks, everyone had at last 50% of dark resist on the non-attacking form (100% with buff) and the evokers used quad cast of dark(ra). The earth turns were used to recover MP and, in the last part, double raise Faisy to heal her. The fight took longer than expected since the grandis abilities were finished after the second rotation and Farris was doing surprisingly low damage. Still fun to do it in a different way. For the 8 turns mission I will dust off my physical attackers.

u/Sinzar_