So...Batman Vs. The Teenage Mutant Ninja Turtles. Part of me still can't believe this movie actually exists, but it does and it's pretty good!
I don't want to spoil too much of the movie, so suffice it to say the basic premise of the film is that The Shredder & the Foot Clan steal some mutagen, go to Gotham City, and team up with Ra's Al Ghul for a supremely goofy plan. The Turtles follow behind them, and hijinks ensue.
What I like about this movie is that there's clearly a lot of deep love by the creators for the different incarnations of both franchises. The art style is straight out of The Batman, Batman's voiced by Troy Baker, who voiced him in the TellTale Batman games. The Turtles designs are straight out of the most recent TMNT series (unfortunately), but Shredder looks like he's sporting a very nice updated version of his 80s cartoon look. The turtles fight a goon who looks just like Krang's robot body suit from the 80s series. Ra's Al Ghul is sporting his Batman: TAS design, and he even has Ubu with him (who very rarely appears in adaptations these days). Penguin's voiced by Tom Kenny, who voiced him in The Batman, but he's sporting a character design modeled after Burgis Meredith.
The animation is excellent as a whole, colorful; fluid; and never off-model. Really, my only gripes with this movie are pretty simple:
1. Damien Wayne is in this movie - apparently, in the original comic, they used one of the Robins that people actually liked, but probably for the same reason the Turtles have their most recent series designs...we're stuck with Damien Wayne as Robin. Gratifyingly, no one treats him with any respect until near the end of the movie, as he deserves.
2. Mutagen doesn't work either of the ways it's ever worked across any of the various Turtles incarnations, which makes the transformations feel really random and REALLY stupid in some cases. It just seems to run on "hey, there's an animal similar to this character", and really falls flat. Speaking of...
3. There's an extended portion of the film in Arkham Asylum, and it's both total filler and REALLY underwhelming. The movie would have been better off cutting it and fleshing out the cast already established at that point.
Overall, though, I really enjoyed the movie. It has a nice tongue-in-cheek tone that works well with this specific pairing of franchises, and the fight scenes are fantastic. And stick through the credits, where there's a really cool thing they do with famous Batman/TMNT comic book covers.