I think this is necessary for obvious reasons. I finally beat the story mode with everyone, and boy some of those boss fights are CAKE compared to others. In order of difficulty from easiest to hardest, roughly:
Peacock
Double
Valentine
Cerebella
Filia
Painwheel
Parasoul
Fortune
Which is sort of funny considering Peacock was built to destroy the Skullgirl to begin with, huh?
Here is what you need to know about the boss fight.
PART 1 - She will toss small skulls, large skulls with tails that will drag you on hit far away from her and hands come from the ground. Unless you’re Peacock, stay close and do heavy normals. If you’re Fortune, you can never use s.MP, c.HP, s.HP, j.HP or qcb+P because getting counter hit in any of those (or doing the last one) drops your head, leaving your head unable to block the skulls. Recall it if it happens. If you’re Cerebella, stay a half screen away and Titan Knuckle (f+HP) your way to part 2. If a tiny skull hits you it serves as an instant recovery so just keep doing that. If your character has an air dash, try doing one hard normal, air dash and another hard normal to make things go quicker. If you’re Peacock, HP into qcf+HP x 3, gain as much meter as you can (2 or 3 is good) then Argus Agony (qcf+PP) once to get to part 2. If that doesn’t get her to part 2, charge up a HP item drop to full while blocking and jumping back (qcb+hold HP) or shoot some guns.
PART 2 - Find one of your character’s aerial normals that does good damage and can cross up. Here is a list of possibilities:
Double/Peacock - j.HK
Valentine - j.HP
Cerebella - j.HK
Parasoul - j.HP, j.HK
Painwheel - j.HK
Fortune - j.HK on super jump, j.LP
Filia - j.HK
You are going to run to get close to her, then jump over her hitting her with your crossup move. Without stopping, you’re going to jump over her again and do the normal again. If she moves, RUN AFTER HER and keep jumping over her. She seems to attack less if you’re jumping from one side to another, and most of her attacks will miss with good timing. If the Mother shadow goes underground, or high above, stop and block, wait for it to come back to Marie, then jump over her, do normal, do it again and don’t stop until she’s blowing up again.
PART 3 - God help you. The good news is that if you did parts 1 and 2 correctly you have a good bit of health, and hopefully in the case of some people, meter.
Peacock - Spend every bit of meter you have by going to the corner and doing full screen Argus Agonies (qcf+PP) until she dies, or j.HP, item drops, George at the Air Show (qcf+HK).
Valentine - j.HP, use all your meter on aerial qcf+PP from the air in front of Marie
Double - Hornet Bomber (dp+HK) into car (qcf+PP) for minimal risk, j.HP otherwise.
Parasoul - j.HP, sniper shots (qcf+PP) cancelled from Napalm Pillar (charge d,u+HK)
Painwheel - Mostly jump at her and do j.HP, j.MP, j.HK
Cerebella - Jump at her with j.HP, j.HK, or do dp+MP or dp+HP (most notably)
Fortune - Never use s.MP, s.HP, c.HP, j.HP or qcb+P for any reason ever; jump with j.HK, or do dp+HK
And so, you have beaten Marie without having to know anything ever. Other than the notation I’ve been using!