Looks like Leila is the current Queen when it comes to zero turn runs in this era.
The idea is to remove as many Speed passives as you can to make everyone as slow as possible. Try to reset until one boss starts first and this starts the train of free turns from Leila.
Once FR gauge is full you can chunk a huge % away in force time, after which Terra can finish the bosses off in her free turns
Timestamp
Party setup at 15:35
If you don't have Raijin call, use WoL
If you don't have Raines or Leo LDCA just use your best HP DMG up Debuff calls.
Kain has BREAK speed up, Critical Speed Up, Gungnir Lite, Jump III Lite and Heaven's Trotting Knight passives removed
Terra has Meltdown Lite removed
Leila has Buff Speed Up removed
You can replace Cissnei aupport with Garnet or possibly Selphie
0:00 Setting Up first FR
Reset until any boss goes first. This will trigger Leila's Counterattack orders.
The whole first phase is getting ONE turn per party member before a boss gets a turn. Be very careful with Breaking the boss or the high turn rate attacks.
At FR gauge 80% or above, use Kains BT+
When bosses hit Force time, use Terra's BT+ on the final force time turn.
Use Leo LDCA on the final force time turn as well.
When bosses get out of Force time, swap Leila out, use Cissnei AA then pop summon
8:22 Summon Mode
Use this to pop Force time, and to launch Kain in the air without increasing turn count.
9:50 Terra BT mode
After this just finish the bosses wkth LD Meltdown
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