Often, Playmates will start a subgroup of the Turtles and end up not finishing it before giving all four of them the same treatment. Usually it's Leo that will get the release first, followed by Mikey and then finally Raph and Don rounding out the end. 
That's exactly what happened with the Shadow Ninja Color Change figures. The Shadow version is just a straight repaint of the original figures from the Nick TMNT line, so it seemed like a no-brainer that all four would see release, but apparently it wasn't in the cards for Raph and Don to become Shadow Ninjas like their brothers. 
These two are seriously some of our favorites to have out and just mess with while watching TV or looking at our phones while listening to TV. The gimmick is neat too, but we don't play in water too much while sitting on the couch, so the black shadows are always present. 
We should mention that Leo actually has TWO Shadow Ninja figures, the first was released as a SDCC exclusive that did not have color-change action or any articulation. Which is pretty annoying that a better version came out at mass-retail for less than $10 when some people probably paid quite a bit for a figure that became somewhat obsolete soon thereafter.

Between filming insurance commercials Mondo Gecko likes to tear it up at the local skate park. 
This update of Mondo looks like it could actually be a Gecko that Playmates packaged and hoped nobody would notice. 
The look of a skateboarder has changed since the last time Mondo Gecko had a skating figure (don't forget he had a hippie rock n roll look in the early 90s too) and this update to the character has followed suit. His board lacks any sort of branding or detail and reminds us of those Muppet Babies figures that were released by McDonald's in the 80s. Playmates probably didn't do this to cut corners, it was most likely to allow for fans to customize the board as they saw fit. 
This guy is really fun to pose and give him random accessories - right now he's displayed with the discman that came with the Austin Powers 2 Scott Evil figure, that paired with some nunchucks from Mikey. 

We don't *think* Donny is our favorite turtle, but his figures keep coming out on top when we're looking at subsets of the Nick TMNT figures. Such as Frankendon here, the other Mutants & Monsters Turtles figures were great - there's just something about this guy that puts him above (maybe the height due to the intense lifts on his boots?) the other brothers.
His electric prod/staff attaches to his back which is pretty neat so he can use his hands to lunge forward at folks that he's just trying to give a hug to.
That snake helmet isn't an actual accessory that he came with - just something we have around the house that looks cool on certain figures. We don't remember what it's from, but we know it's something stupid rare. You'd have to ask Steve what it is. That's what we did.

Grouping these guys into one post as they're hard to pick a favorite from and we don't want to post a bazillion times.
The detail on all the armor is super impressive and Usagi's ears pulled into a ponytail is such a nice touch. The turtles look like an elite guard with their masks on and we just noticed we didn't take any pictures of them with their masks off - but that's not a huge deal since we're assuming you guys all know what the turtles look like at this point.
So great how the individual Turtles weapons translate into these samurai versions along with their unique headdress symbols make these guys super fun to have displayed. This series was a highlight of the toy line. Very glad they were able to secure the Usagi character for release. There was also a more traditional Usagi released as well as a repainted version of this armor with a horse.
Stan Sakai was also able to work out a deal with Playmates to release a repaint of the normal Usagi on his own site which was also a nice surprise. I believe those have all sold out, but you may be able to find one on the secondary market.

We almost didn't have enough room in our photobox for these two. Also, we're kinda breaking the rule here by including two movie figures, but this is a stupid list on a random blog so no one cares.
These guys were the first purchases from the second movie line - though our dip into the movie figures only consisted of them, the regular 4" versions of them and the 4" Krang (who should have made it onto the list but honestly we forgot...). 
These two figures look almost identical to their 4" counterparts - which is surprising when you realize how much articulation they have. So much detail on these guys really makes for some great display pieces. 
Also worth noting Bebop's muffin top is the best thing we've ever seen sculpted onto an action figure.

Casey Jones is a staple to the TMNT line and this iteration of the character was a great one. We're glad they didn't release him without the hood and mask initially, though he later saw a release without the hood/mask paired with a vehicle. 
The fact that he has his face paint on under the hockey mask is amazing, even if he loses the mask during a fight, he's still able to hide his identity with his Misfits-looking face paint. 
The little piece on his back that holds his hockey stick and baseball bat likes to swivel quite a bit so it's a little frustrating when trying to pose him and they turn upside down because of the weight. 
​Still, he gets to be on the list because he's wearing what Sam would like to think he'd look cool in if going into a purge situation. 

Tiger Claw put us through a rollercoaster of emotions from the moment we saw him getting super excited to have a tiger figure, to the realization of opening him and finding his limited articulation really bummed us out to taking pictures of him a year or so later for this list to find that he'd really grown on us despite those articulation problems. 
Really it's just that there's no joint or movement on his arms below the shoulders that disappointed us. For a character whose weapons are pistols, it's frustrating to have a limited range of motion on the arms, hindering where he's able to aim them.
But he's a freaking tiger with guns and an eyepatch! That's enough to get him on this list despite any points against him.

Mozar is the only Triceraton offering from the Nick TMNT toy line where the 2003 line had a few. But any Tricertaton is a welcome addition to our Turtles collection. When shown at Toy Fair he had a few more paint apps, most notably the silver boots that were now released  in solid orange. This is easily remedied with a silver Sharpie. So easy that we still haven't done it to our figure.
He didn't come with any accessories, which is kinda lame - but Playmates is all about saving dollars wherever they can so it's no big surprise. Plus if he's supposed to be a General or whatever he might not need to actually use a weapon. 

TO BE FAIR, we never said these would all be figures released by Playmates. Though they hold the license for Teenage Mutant Ninja Turtles action figures, they aren't responsible for #18 on our list - the Kraang robot that was released by Sonic in 2017. 
Sonic had a short-lived TMNT promotion for their kid's meals that included seven figures that all shared this exact same mold, a few non-figure items.
The translucent ice-blue on this figure along with the design of the character (seperate from the mold itself since that's shared between each figure released in this series) really make this the stand-out figure from the Sonic offerings.

Yet another instance when looking a subset of turtles that we decided that Don got the best treatment out of all of them. This Donatello is straight up creepy and if released as it's own figure outside of a TMNT toy line, would stand alone very well. 
The purple is amazing and the weapons (how creepy is rope as an accessory when paired with an ax and a sledgehammer??) make for a very menacing figure. And that's not even touching on the skull mask and hood. Oooooh - someone should do a Skeletor custom with this figure.