- Author's Saving Throw: Unlike the Lighter and Softer approach of the previous film, this one actually has the turtles use their weapons and actual martial arts in combat, as well as having a more serious story.
- Awesome Music: The movie has ZZ Top's "Can't Stop Rockin'" and Baltimora's "Tarzan Boy," both '80s chart toppers.
- He Really Can Act: Elias Koteas does an excellent job as both Casey and his (possible) ancestor Whit. Some viewers even questioned if Whit was indeed played by a separate actor.
- Hilarious in Hindsight:
- At one point, Walker is referred to as "Zorro dude". Stuart Wilson would go on to play the Big Bad in The Mask of Zorro.
- Near the end of the film, the Turtles bluff Walker and his men into thinking they're Immune to Bullets, and that their bullets would just bounce off and kill them instead. Come the next live-action film, and in that continuity, their shells really are bulletproof, and bullets do bounce off.
- Replacement Scrappy: Walker is considered a major step down from the Shredder.
- Sequelitis: Mercilessly panned by both critics and fans alike; the movie featured an outrageous plot even by the franchise's standards, an uninspired villain, fewer fight scenes (although the fights that are in the movie are longer and more elaborate), and costumes/animatronics that looked unbelievably cheap due to the absence of Jim Henson's Creature Shop. There wouldn't be another Ninja Turtles movie until the franchise was rebooted in 2007, and no live-action movies until over twenty years later.
- Special Effect Failure:
AVGN: "He looks like a puppet that should be used on Sesame Street!"
- Walker's death, where he falls to a watery grave without making a splash, apparently just disappearing while making a splash sound. After examining this failure, AVGN noted that if the crew didn't want to spend extra money on animating a splash, they could've cut to a shot of the turtles watching the plunge as an off-screen splash is heard.
- The turtles and Splinter look a lot more cheaply made this time around. The turtles have mouths that move too quickly and robotically, visible seams where the neck meets the headpiece, eyeholes under the bandanas that are just slightly visible in half the film, giant overbites, and poorly blended spots on their bodies, giving them a more rubbery, cartoony look. Splinter is a very obvious robotic puppet, as opposed the advanced hand puppet of the first two films, that was seemingly only built from the waist up, as the viewer never sees his legs like they do in the first two* and has poor lip-syncing between the voice and the animatronic mouth movements. This is largely because of the Jim Henson's Creature Shop not returning for the film, and a company less experienced in creature effects, Eric Allard's All Effects Company (who are better known for their robotic and on-set effects work in the likes of Short Circuit, Class of 1999 and Demolition Man, to name a few), taking over instead.
- Spiritual Adaptation: This movie felt more like an Usagi Yojimbo movie than it did a Ninja Turtles movie.
- Tear Jerker: The film comes close to one at the end when Mikey admits that he would rather stay in the feudal Japan of the distant past, which he actually finds preferable to the 20th century, where he has to live in a sewer. Raph and even Leo agree that they feel better off in the past than in their own present. It's a rare moment where Mikey steps outside his usual "party dude" persona and shows a different side of himself.
- They Wasted a Perfectly Good Character: After being absent from the previous film, Casey Jones returns to...babysit some Japanese guards. He doesn't even fight anyone.
- They Wasted a Perfectly Good Plot: It's the TMNT fighting in feudal Japan. A concept that could have been awesome if put in the hands of competent filmmakers.
YMMV / Teenage Mutant Ninja Turtles III