Easily one of the best games I've played this year! Just finished a Pacifist + Mirror First challenge run after my 100% playthrough yesterday (almost got Speedy Boy too, off by juuust a few minutes) and the routing was just bonkers, not being able to break any of the kill blocks past the first completely turned the game on its head and showed just how open-ended and well thought out the level design is. Sequence breakingbashing!
The wording "less than 10 kills" had me sweating bullets when the kill count went up to 10 at the final boss, I'd recommend changing it to "just 10 kills" to be more clear and also make the run objective obvious (4 regulars for the first kill block and then the 6 bosses only).
I'd love to see a sequel or DLC with Jerry, this game seriously rules and the only problem I have with it is I'm going to still want to play more of it after getting all the achievements!