First of all, YES, I'M BACK FROM THE HELL OF LOCKED-OUT-FROM FACEBOOK. HAIL GUMI FOR GIVING ME BACK MY ACCOUNT. (Though it would be nice to have another system for login so this won't happen again)

Now, back to the battle. I said before (that's when I still can't login) that I wanted to do it with Garnet, Rosa, Tim, Sakura and 2 Edgar. Well, no one in my friend list set one of those so I decided to remove Tim and put World Destroyer on Rosa. (-50% MAG would be much better to ensure that I survive Eschaton.)

WE 5* META NOW (Imgur Album)

^{just kidding}

Party: Garnet - Odin, Sakura - Lakshmi, Rosa - Titan, Edgar - Carbuncle, Edgar - Shiva

Some RNG are involved. I'll list them here:

• High Seraph hitting a character more than thrice will most likely fail the run
• Fill Rosa LB by 8th turn (to restore Sakura's MP after mute)
• Fill Esper gauge by 10th turn (And Garnet's LB too so it's faster for the second summon)

Not difficult to fill them up when you chainsaw every turn while Garnet helps auto attacking.

Some reasoning for the equipment:

• Giving everyone sleep immunity to prevent Grand Cross from screwing your run
• Giving Garnet Survival Edge so that she can deal damage to generate LB and Esper orbs. (because of the element) Add Second Knife to generate more.
• 2 EVO MAG 10% so it's just enough to kill the Seraph in 2 summons (tested those on the dummy because they have the same DEF/SPR)
• Giving Sakura all those important abilities because she's the most free
• Make sure that Sakura is not the one with the highest MP because she need it. Getting hit by the second Mute is ok because of Rosa's LB.
• 2 Edgar with elemental weapon to chain and just give everything for survival. Nothing special
• Giving Rosa the World Destroyer to break Seraph's MAG to survive Eschaton, Siren's Robe for sleep and silence immunity.

The strategy:

• Edgars basically just Chainsaw every turn and block if necessary
• Garnet just auto attack until the 11th turn when she starts the summoning
• Rosa have the Bless (enhanced) - World Destroyer- Free action rotation
• Rosa to use her LB after the second mute, use Bless in the 10th turn before the summon and to use World Destroyer after the summon
• Sakura is a bit complicated: Defensive Barrier (enhanced) - repeat - Blighted Gloom (blind resistance up) - Manufacted Nethicite - Waking Protection (paralysis resistance up from Lakshmi) - Free action (Defensive Barrier) until the 10th turn to do Manufacted Nethicite again

I'm aware that the picture of the Odin chain is not clear. Here's two samples from my test run. one, two

Can't wait for the Hallowed Father of the Eidolons. :D

UPDATE

u/HappyFrisbees is kind enough to lend me their Tim. It's now much easier. Less RNG and Rosa is now free to heal whenever she wants to. Eschaton damage is reduced from ~3k with World Destroyer to <2k with Tim's break.