Let's start with art again, because that's where this issue excels. The opening pages are designed to mirror Casey Jones trip to the hospital with Leonardo's captivity with the Foot clan. It's a neat trick; okay, so it's not "Fearful Symmetry" from Watchmen, but it's still pretty cool.
The next art trick is cooler, though; as Kitsune uses her powers to brainwash an unconscious Leo, we see his dreams; the entire run of the comics is redone, with Splinter as the villain and Shredder as the hero. The really cool thing is that each of the former artists who originally drew these storylines return to draw the warped versions. Can't believe I'm so excited to see Andy Kuhn back.
This story is mostly told in flashback; the device used by writer Jason Ciaramella is Old Hob telling Slash his story as they wait for their introduction in issue #23. Hob doesn't want Slash's sympathy, he tells him. He just wants Slash to understand where he's coming from.
Hob isn't exactly a big fan of humans; he was thrown out into the snow after being a pet to a small boy who was a bit forgetful about his kitty litter chores. It's a pretty old story; furries have seen this one before, hundreds of times. Except, this time, instead of learning to trust and love again and finally reuniting with another, kinder owner, Hob attacked some odd turtles, and became a cat man. The human who takes him ends up being Baxter Stockman; Old Hob didn't exactly end up any better in that case, what with being shot and all. It's a standard origin story; the only real twist is that it's supervillain and lost pet at the same time.
Dave Wachter is on art; his Old Hob is maybe a little too human most of the time, but the muted color palette (along with the narrative device) imparts an odd noirish feel to the proceedings.