Crack Cocaine of Dawn (Dawn Office S3 spam)

With proper piloting, this team can have Faust and Gregor use their boosted S3s every second turn once you get the cycle rolling

Doubleslot Sinclair because he gets the most value out of it, and you need his followup attack gimmick to maintain the stack. Always hold an S3 on the dashboard, you WILL need it.
Use whatever you need to get Faust and Gregor to (at least) 24 stacks, but don't defend on Faust until you get here. Faust must be faster than Gregor, but you can usually solve this thanks to having speed boosting supports on Don and Ryoshu.
If you really want to run this in a gamemode that doesn't allow doubleslotting, just bring a random Tremor ID you like in place of one of the benched Sinners. Do not expect the cycle to be reliable in this case.

On the turn everything falls into place (usually turn 4, though optimal RNG in the form of Faust and Gregor getting their S3s can allow for a turn 3 setup), use defense skills on both of them. Leave a weak skill that does not target Gregor unclashed (so he can use his Assist Defense against it).
Faust gets 6 stacks from the once per encounter gain on her defend, reaching 30 before she would use it. She thus gets Dismemberment at High Noon and its many benefits, most importantly 3 Battle Instinct.
This gives Gregor a followup, which will certainly be worth 6 stacks, bringing him to 30 as well by the time he uses his own. Crack of Dawn triggers, he gets Dawnherald onto the team. His assist defense gives him 5 stacks. Faust follows up on this, getting 4 stacks out of Seconded Offensive.

On your off-turn, you will be looking for the following:

• Gregor has his S2 or S3 in queue
• Faust has her S3

If neither of these is true, whip out Sinclair's saved up S3. With his base skill and the followup attack he gets from the S3, Gregor is sure to build 15 stacks, leaving him at 20 by the end of the turn.
Faust will get 9 stacks from her Battle Instinct, and at least 8 stacks from her skill of choice. This puts her at 21 stacks.

On the next turn, Faust gets 9 stacks from her Battle Instinct, letting her use her enhanced defense again, and the followup that stems from this brings Gregor to 30 as well. Repeat ad infinitum (don't forget the Assist Defense) or until the enemy dies.

Due to the benched Yi Sang and the Dawn Office effects available, Sinclair heals 20SP every turn and thus will constantly be maxed out on SP, so he's all good.
Thumb Meursault is negotiable: if you like him more, Hornet works fine as well.
If you don't like having to bother with holding an S3 on Sinclair, just give Gregor the doubleslot instead. It's a bit less efficient on damage from what I've seen, but piloting it needs absolutely zero thought.

You can't actually squeeze Everlasting or Unbrilliant Glory into this without disrupting the cycle, so don't bother unless you desperately need it.