Boom, all six of the 4* magicites mastered, Tiamat down! Bring on the Holy / Dark bosses!
Team I used to beat Tiamat in 54 seconds:
Onion -- Entrust, Wrath -- pUSB
Alphinaud -- Curaja, Protectga -- SSB
Arc -- Curada, Shellga -- SSB
Relm -- UltraCure -- BSB
Squall -- Snowspell Strike -- BSB2
Magicites: Wendigo, Isgebind, Taharka, Krysta, Gizamaluke
Video of my kill:
Tiamat 54 sec
So this fight is completely retarded and dumb, let's get that out of the way. I had to go farm 4 copies of Krysta and Gizamaluke just to not die in the first 10 seconds of the fight, and I also had to run 3 healers, with an entrust battery feeding nonstop soulgauge, so you may as well say 4 healers.
Squall did most of the damage with his bsb2, with some extra added in from radiant shield. Relm gave last stand and kept using CMD1 of her bsb for instant heals (mostly to charge her soulbreak faster for more medicas). Alphinaud was a support healer, but the true star of the show was Arc with his SSB (instant medica + pBlink). During phase 3 when the boss does one ridiculous AoE after another every 1.2 seconds Arc kept everyone alive (with onion feeding him entrusts).
I don't like this fight and hope the person who designed it feels bad.