DFFOO[GL][Trey LC] Cor abusing Ashe's buff and Galuf's counter battery
23Reduction: 70/30: Brv dmg/Brv Gain
Since Ashe's buff only depletes with active turns, Cor's preemptive strikes can maximize the benefits of the fat extra HP dmg up on all of his off-turn attacks without having to worry about the buff running out. This is especially profitable when you come up with a boss with increased turn rate, AoE attacks. By taking advantage of this buff, the attack does more dmg overall and the refund would be bigger for the next attack.
This is even more advantageous when you have someone that offer battery in the off-turns. Galuf's skills, counterattacks give the entire party battery. So again putting Galuf or anyone with constant battery potential benefits Cor significantly.
The interesting thing about Cor's interaction with Galuf is that it is not really as braindead as it seems. It appears that Cor's preemptive strike only triggers when the initial target has the buff. In other words, you cannot put Cor's buff onto Galuf and expect Galuf's counter would trigger Cor's attack. (e.g. Only by putting the buff onto Ashe would trigger the attack when Ashe is targetted, even though Galuf is actively stepping in to become the target). Only the initial targetting of the boss matters. Luckily Ashe's Queen's Order manipulation can alleviate the stress of facing a relatively fast boss that jump in the queue with turn rate. It is unlikely that you can cover 100% of the boss's attacks if the targetting does not have a criteria (e.g. certain bosses targetting the highest HP ally), but realistically you can cover Cor and another one at all times, so only when it is the case of one targetting Ashe and one targetting Galuf would result in partial coverage. It stays true that in general the more turns the bosses get the faster they kill themselves.
Another thing about Trey's LC is when the boss is covered in yellow aura, they require force break to be dealt normal Brv dmg again (and it prevents launch as well). That's when Cor's rainbow number inducing Reaper's Gale at 10 stacks come in. Having a high Brv cap means he can 100% shave off all the Brv and break the boss to dispel the aura. Same can be done to the other bosses like the bears in Ciaran's chapter or the upcoming Gladio LC. Even should one use fail, you can just pop a LD and do it again. They are all instant turn rate attacks anyway so fire away!
Overall while the Galuf and Cor targetting interaction is not as braindead broken as expected, they are still great partners. Putting an aura bot like Aerith/Pecil, or a potent buff such as Ashe's on Cor are some of the most abusable synergy you can do with him. As long as you give him some support he is perfectly fine in high reduction fights. After so many test runs on different stages I think using him efficiently would generally cut down your stage runtime and turn count by a large margin. This one clocked in around 9:49 and I really pleased with the result, even though the team is rather passive than some hyper aggressive turn hogging comps.