What is the infinite turn? Check out that video!

Basically it's a specific setup that allows you to hit the boss (until it runs out of health) without giving it chance to have it's turn.

Sounds disgustingly broken? Great! Just check out the sections below for more info on how to set this up and try it for yourself.

There are 3 EXE drive skills that delay the enemy's next turn.

They are: Uni's NGP, Neptune's Neptune Break and Blanc's Hard Break

There's one regular combo skill that delays the turn as well: 5pb.'s Slow Speed

Disclaimer: This is the way I set up my party, I do not insist or imply that this is the best or only way to do it. Multiple "solutions" exist to this problem, and as such it is entirely possible to achieve the same infinite turn without following this.

You want to have Neptune/Uni go first preferably. This isn't hard to do, since they naturally seem to be just about fast enough to go in roughly that order.

Blanc's combo setup is largely irrelevant. Set it to whatever you want. I used turn speed +lv4 on her because blanc is horribly slow.

Uni does all the rushing in this setup. You want Full Clip x3 as rush and Tricolor Order. Technically you could add other high hitcount EXE finishers (that have higher charge requirement) for extra charge overall, but I found it sufficiently reliable with just tricolor order.

Neptune uses Nep Slash x3 and dual arts. Once again, dual arts is chosen because it's pretty efficient for it's cost.

5pb. uses Slow Speed and Slow speed only, followed by infernal blow as EXE Finisher because it's the most hits we get for that cost. She also has a turn speed +lv4 chip on her, because we want to be able to use Slow Speed as often as we can.

As for partner setup, we use anyone we can get our hands on that has "Cooldown Reduction" as their shared partner ability. This means we use Vert, IF, Rom and CyberConnect 2. You can pair them in any way you want. It does not really matter. Do note that CyberConnect 2's "Null Category" is very important against most robot machine type monsters, so that's about the only one where some additional consideration must be had.

The combo goes something like this:

Cycle 1:
Uni: Full Clip x3 + Tricolor Order
Neptune: Neptune Break
5pb.: Slow Speed x3 + Infernal Blow
Blanc: Hard Break

Cycle 2:
Uni: Full Clip x3 + Tricolor Order
Neptune: Nep Slash x3 + Dual Arts
5pb: Slow Speed x3 + Infernal Blow
Blanc: Hard Break

5pb. always uses Slow Speed x3 + Infernal Blow. NO EXCEPTIONS

Blanc always uses hard break.

Uni always rushes with full clip into tricolor order. Only exception is if you are in a really bad position (i.e. boss about to attack and a single attack spells death for any member)

Neptune alternates between rush and Neptune Break. This is the only real thing you have to "think" about when executing the combo. Against slower bosses, you may be able to use 2x neptune break before 1x rush. Alternating is still the most reliable strategy most of the time, as it ensures you do not run into a EXE charge deficit too quickly.

Our EXE Finishers are crucial to charge building, as such we need to have around 2-3 EXE drive gauge before we can start this combo. This affects reliability of this combo in Colosseum bosses. For these fights, it's all about having a good setup to allow you to start the combo without everyone being dead or require constant heals. I have yet to find a consistent setup for Delphinus though...

Thanks for reading up to this point!
Hope the guide was useful :)

Screenshot used in the thumnail is Delphinus, extracted from my second clear of it: Video Here

Feel free to check out my Re;birth 1 guide here: ALL EVENT BOSSES with Fortify Enemies - An In-Depth Guide to Nep
It contains some detail about the game mechanics, which is shared in both Re;birth 1 and Re;birth 2 (Also probably for Victory as well, but don't quote me on that)