The story had a few premises that diverge from the main narrative. For one, Cauldron has a black market where you can buy the vials that give powers. As with the main story, they can't pinpoint powers, but they have a good idea as to what vials give what kind of power, and how much risk was involved. There's also a plan where you can pay for someone else to get powers, with part of the payment going to them, and they're under contract to be your nemesis for a specific number of incidents, I think with some ability to impose upon them what the incidents are. Emma chooses Taylor. Secondly, there's a "comedy hero" or "comedy villain" designation which is respected by most heroes and villains, involving heroes and villains who avoid great harm to others, and focus on entertaining with cheesy one-liners, puns, and ridiculous escapades. Mouse Protector is a well-known case of such a hero.
I think Emma gets some sort of gem-based powers, the ability to summon the gems and grow them out in particular patterns. Taylor is given a vial which has a high risk of mutating people into monsters, but comes out of it with biomanipulation powers, I think limited to insects, with her managing to convince the Cauldron representative (Doctor Mother?) to put down the listing as the most innocuous aspect of the power, being able to control and mold insects. Taylor then becomes the Bee Queen, or maybe Queen Bee, something like that, a bumbling "supervillain" whose bee minions are generally incompetent — I think she even refers to them as "bumblebees" as an allusion to it — with tons of puns and a vague focus on environmental protection as an excuse for the robberies. Because she's playing a "comedy villain", Emma has to treat her as such, and keeps getting foiled, in part because she doesn't know that Taylor can turn herself into a swarm of insects and fly away. Emma becomes progressively more violent, despite warnings that it doesn't read well, and that it could break their contract, leaving Taylor free to do whatever she wishes.
I don't remember how the story ended, or even if it has when I stopped reading it, probably about 2-3 years ago. It would have likely been on the SpaceBattles.com or SufficientVelocity.com forums.