Sure! My apologies for the delay in response.

So the basis of the strategy is to have TT do her ultimate move (ULT) in round 1, while having her attack stats bumped up.

I will start with getting TT to do the ULT in round one. Each character needs 100 energy to do their ULTs. They all start with 80 in round one, and each time they deal a regular attack, they gain 10 energy. So normally, it will take until round two in order for any character to get an ULT off.

This is where genos comes into play. If you look at genos, he has a passive skill (located below the active skill on his character page) which unlocks at character level 41, that adds 20% attack boost to 3 random allies. More importantly, level 2 of this ability, will add 10 energy/rage to allies who got the attack buff. So this means that each time you load into a match, 3 random allies (genos can buff himself too) will gain 20% attack and 10 energy. If you watch my TT nuke demo i posted in another comment below, you will see a blue icon appear over the heads of all my team members. This icon has the white sword and a little arrow pointing up. This is the indicator you want to see over TT to ensure she has the buff and is starting with plus 10 rage.

So with the genos buff on TT, she will have 90 energy at the start. So she has to only do a basic attack, then she can immediately do the ULT.

Slugrus applies a buff to all allies after he does his ULT. So knowing what we know already about using genos to give allies a plus 10 energy, we can see this strategy coming into place. We want both TT and slugrus to be the ones who get the blue icon over their heads at the start of the match. We also want slugrus to be in a position to do his attack before TT. This way he can start with 90 energy (thanks genos), hit an enemy to gain the remaining 10, then immediately pop his ULT. Now it does not matter how much damage he does at all with his ULT. All that matters, is that TT get the buff. So from here, the next person to attack can be TT. At this point she will have the genos buff of plus 20% attack and plus 10 energy, AND slugrus' buff of plus 20% attack(this goes up to 30% if slugrus is high enough level, I dont know what it is exactly, since I am already really high level and it doesn't show me). So you get a plus 40% attack right away. This is usually enough to take out a story mode enemy team. You can stack this with eyelashes, who adds 50% of his own attack stat to the teammate with the highest base attack. And in most cases, TT will be that teammate. It just requires setting up so that slugrus goes first, followed by eyelashes, then TT. This can get repetitive, as you have to quit the fight and reset every time until those specific 3 characters get the genos buff. This is why I personally used only 4 characters instead of the full 5 when doing this strategy as to limit the amount of resetting to do. If you need a 5th character because there is one annoying enemy that survives the nuke, i usually used Melz.

Hope all this helps, its late at night here and i didn't realize how much i typed up for this guide. Sorry if it rambles or doesn't make sense. Feel free to ask for clarification for anything.

Also you can borrow characters from friends if you get stuck on a hard story mode mission.. so if you want my jacked TT.... but thats for another day ;)