i have yet to work out my dearest beloved anon HOWEVER it's one of those things where father alexander leads a group similar to how sonya does. he sees alex as a martyr of sorts for like, all that is wrong with the city and how the city has imposed its will onto him and sees him more as an example to be saved rather than a person, while alex just thinks he's a general nuisance but still grateful for his sympathy from a place of having yknow, clockwork orange karma ripping everything away from him

he leads the gang specifically alex through the dungeon before taking alex and separating him from the group, so you just go through that entire dungeon regrettably to get him back (though it can be said you need the golden bough at the end anyway soo) and find him like violently torturing alex with music from his past (singing machine aberration?) in an efforts to get him to kill himself which is VERY much working. rambles to the party about how they should leave alex to be "saved", if they truly care about him they'd leave him for dead. unfortunately no one in the gang does care for him so they save him.

golden bough is in the singing machine aberration, which is opened because alex commits suicide and feeds himself to it mid-battle as you're taking your time trying to deal with father alexander and his gangs (phase 1) and their music-posessed buffs (phase 2).

alex is revived and pulled out of the wreckage with something uncharacteristic (permanent scar on his neck)

Arsene: Ultimate Thief
Montressor: Ultimate Sommelier (still canonly has killed a man)
Samuel: Ultimate Sailor
Alex: tbh. he'd also be an Ultimate Delinquent kinda guy (he's also the komaeda. unfortunately quite smart and butts heads with the protag [alice])
Yuriko: Ultimate Physician (faux komaeda)
Van Helsing: Ultimate Polymath
Emma: Ultimate Matchmaker (au where she's a good matchmaker. still annoying as hell though you do NOT want her input)
Alice: Lucky Student (main character)
Charlie: Ultimate Scientist (the horrors.)
Zaroff: Ultimate Hunter (Mastermind)
Cheng Bo: Ultimate Vigilante
Hyde: Ultiamte Philanthropist

this is in collaboration with my boyfriends limbus bus (our buses are combined into a two tier bus). the only ones that survive for me are Cheng Bo and Alice. i need to remember our convo but i think it was like,

T1 Yuriko is killed by Emma
T2 Arsene is killed by Grenouille (BF character), Cheng Bo tries to help him cover it up and fails.
T3 Montressor and Van Helsing are killed by Hyde (crazy danganronpa breakdown)
T4 Charlie is killed by Samuel (really sad trial where it was an unfair circumstances that lead them both to agree this had to be done)
T5 Claire (BF character) accidentally killed by Alex
T6 Zaroff reveal

god bless you anon im going to have the worst time of my life. /pos of the existing ones:

arsene: sunshower
montressor: rime shank, wishing cairn
samuel: ya Śūnyatā tad rūpam, fluid sac, dimension shredder
alex: screwloose wallop, AEDD
yuriko: roseate desire
van helsing: sunshower, capote
emma: pursuance
alice: capote
charlie: impending day, screwloose wallop, hex nail
zaroff: AEDD, lifetime stew, red eyes

of general lobotomy corp abnormalities:

Arsene: Old Faith and Promise, The King of Greed (Gold Rush)
Montressor: Nosferatu (Sanguine Desire), Fairy Festival (Wingbeat)
Samuel: 1.76 MHz, Knight of Despair (Sword Sharpened with Tears)
Alex: The Dreaming Current, Forsaken Murderer (Regret)
Van Helsing: Der Freischütz (Magic Bullet), Red Riding Hooded Mercenary (Crimson Scar)
Emma: Army in Black, Melting Love
Alice: Laetitia (Laetitia), Void Dream
Charlie: Scarecrow Searching for Wisdom (Harvest), Behavior Adjustment

arsene: henriette (mother :>), valorbe (old corp manager, likely working as an antagonist now. remember arsene is a star of the city and stole singularities for the people), ganimard, madame barry (arbiter)

montressor: [in U corp] fortunato , luchresi, prospero [U corp manager?]

samuel: [in S corp] to-be-named crew. otherwise, samuel has been alone with the transportation of aberrations/abnormalities, the "albatross" being what saved her.

alex: [in M corp] dim & pete ("friends"), brodsky & branom (M corp scientists), father alexander (likely helps team in the dungeon only to betray them, more specifically alex)

yuriko: [A corp, but doesn't take place in A corp] Mandala, Shiratora, Usuki

van helsing: [Nosferatu's Castle] jonathan, mina (bloodfiend), our boys arthur, quincey, and john [otome bachelor party team. probably fixer office], nosferatu. honestly think something went wrong in the nosferatu search.

emma: [in T corp] henry (father, antagonist), knightely (madly in love with her), harriet (friend), churchill (antagonist, working with henry). to put it simply she's living in a timeloop

alice:[Index territory] i'm going to have to get back to you on this one.

charlie: [old G corp] kinnian, nemur, strauss (all researchers). frank and joe (coworkers that bully him). algernon shaped boss battle

zaroff: [in R corp, "rattlesnake"] sanger rainsford (something yaoi is going on), ivan (something yaoi is going on).