This could possibly be done in 2T without use of Kam'lanaut BT+ but I decided to just go the extra mile since Odin is pretty beefy with 110m HP
The idea is to take Odin down to zero before he hits 79% because at that threshold he will warp turns.
Timestamp
Party setup at 7:08
There is no alternative call to Raines and Kurasame. You could try a Selphie friend if you don't have Raines but your damage will be lesser without Garnets auras.
Machina FR 30 with 5/5 UW (Raines LDCA)
Kam'lanaut FR 30 with 2/5 UW (Kurasame LDCA)
Penelo FR 13 (Seymour LDCA). Seymour can be swapped with anything else that has HP DMG up debuffs such as Raijin or DKC.
Garnet friend
0:00 Setup
Reset until Kam goes first. Use calls and BT+
Machina use Raines calls targeting Penelo and then AA and BT+
Penelo dances and uses calls until FR and summon is fully charged
Swap Penelo out for Garnet
Use BT+. Ideally should summon and THEN only AA. I went AA first.
2:56 Summon Mode
Position Machina to have final turn but making sure both Kurasame and Raines LDCA auras still up.
Use Kam'lanaut FR midway through
Use Machina LD on final turn inside summon. Then go BT mode
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