Rampage: You don't fucking get it, do you? Glory: We're her friends, Lacunae: That means... P-21 She doesn't have to fight alone!
Following the destruction of Stable 99, Blackjack - teetering on the edge of the Despair Event Horizon - inadvertently gets in contact with DJ Pon3/Homage, who makes a point of showing BJ all the good she's done.
Shortly afterwards, Spike's last-second intervention, preventing Blackjack from killing herself. He goes on to restore her will to live by showing her the Gardens of Equestria.
After a bloody and tragic battle, Lacunae stops to cremate the corpses. Notably, she explains herself by criticising her own Hive Mind.
Blackjack: What are you doing? Lacunae: What a Goddess should.
Chapter 34. All of it. Especially the moments between Blackjack and Littlepip.
P-21 finally admitting, both to Scotch and himself, that he's her father. He sings to her, with Blackjack, Glory, Lacunae, and even Rampage joining in. And at the end, Scotch starts to cry under her bandages, and he wipes the tear away, causing her to whimper "Daddy..." before they hug one another.
Despite her anger with Blackjack, Glory takes the time to make sure that she is feeling better, physically and emotionally, before she kicks her ass for cheating on her.
In Chapter 51, Scotch Tape gets her cutie mark. P-21 immediately comes over and gives her a hug.