She's the Ark of Hacks, C.S-Chan.
The fight is as follows:
1st fight: Destructor, Katana Max, Gigantinger
The FIRST THING that WILL HAPPEN is that Destructor immediately fires a big rocket at you dealing high damage. this WILL kill you if you have anything below 200 hp. I suggest you buy Air Loop/ Accele Roll beforehand and take to the air and use it to get out of the way. Accele roll is better than air loop for this case.
Destructors behavior: Destructor will always turn around to face you, charge up then release a single big shot. Dodging can be quite a pain, so try to stay behind Destructor when attacking. Melee recommended.
Gigantinger's behavior: Gigantinger will continuously rush you and multi-punch you. If you're not careful he'll corner you and take you out. Try to keep your distance. However, due to his kamikaze attitude it's somewhat easier if you used Artillery against him.
Katana Max's behavior: It gets close to you then gets slashing. Sounds easy? No! apparently it has a special status infliction called "shock", which disables all sub-weapons for set period of time. Oh, and he hurts. Keep your distance. Air recommended.
2nd fight: C.S-Chan
If you're playing one-star, this is the last fight.
C.S-Chan is SMALL. VERY SMALL. homing missiles from say, Sturbanger will not be able to hit her often. Try to go with someting with a big blast radius (e.g middle bazoooka), or something that shoots quickly (e.g gatling bazooka).
She runs around during this fight spamming star shaped projectiles, like the one shot from Elme.S HD. Avoiding them can be a little tough when she's after you, but a bit of dashing can save you most of the time.
When her hp runs low you will have to rush her for the last of her hp, because she will kamikaze and blow herself up in a blast of pink.
If you're on one-star, this is the end. If not, read on.
3rd fight: Volcanis, Alpha Golem, Gigandroff
Great, three bosses from the mission Gigan Busters. They're sized down this time so that they fit into the room.
The fight goes pretty much like the fights in Gigan Busters, except Gigandroff is permanently stuck in his "Second phase".
Volcanis behavior: It has two attacks: tiny fire-bird spamming, and a body-slam. due to it's size, avoiding the slam can be quite difficult. Try to fire at it's side/back all the time. Artillery recommended.
Alpha Golem behavior: It's slow. Very slow. However, it takes very little damage from ranged attacks (1-3), but takes regular damage from melee. If you stay in his sight for too long, it'll fire about five or so bazooka shots at you. Deals quite a bit, so watch out. Melee recommended.
Gigandroff behavior: It doesn't teleport, thank goodness! Anyway, it'll try to cut you apart with its sword, fire a gravity ball that slows you down AND deals heavy damage, and then fires a spreading, shotgun-like blue projectile. Avoiding it is easy if you're using an AIR bot. Try to take it down fast! Air/Artillery recommended.
4th fight: C.S-Chan
If you're playing two-stars, this is the last fight for you. IF you're doing three-stars, just keep going.
C.S-Chan won't be any different in behavior from last time, she'll run after somebody firing her weapons, switching targets occasionally, then exploding in pink again when her hp goes low. This time, though, she has a staff that shoots homing projectiles. Also, she fires twice as many star-shaped projectiles! Be careful on this one.
5th fight: Berzelius, Fractulus, Demonfox Haku
Pray to the gods that you'll survive, because you're facing all three at the same time.
While I did not have a chance to get to this part of the fight, I was told that Berzelius will spam missiles, Fractulus spams blaster shots, and Demonfox Haku will attack up close with his swordstaff.
The idea is that Air-types bring blasters to fight Fractulus, Artillery types focus on Berzelius, and Melee bring Combination/3-way daggers and fight Demonfox Haku. Yes, that means you have to beat them at their own game.
6th fight: C.S-Chan
Supposedly the end of the fight for three-star players. However, I don't know what she does during THIS fight, and input is appreciated.
Drops:
Tune-up materials aside..
C.S Rod drops from two-star
C.S Group Fan (?) is an accessory that drops from two-star
no idea whats on three-star.
