The following contains major spoilers for Teenage Mutant Ninja Turtles: The Armageddon Game #1, available now from IDW.
The Teenage Mutant Ninja Turtles have always been plagued by menacing enemies, often in the form of even more intimidating mutants than themselves. In fact, the Heroes in a Half Shell have even faced off against more than a few fellow Turtles over the years, and they are poised to do so all over again. It turns out that the latest generation of mutant Turtles is nothing like their predecessors. Or rather, they are nothing alike apart from their looks, which is all it has taken for them to ruin the Splinter Clan's heroic reputation.
Teenage Mutant Ninja Turtles: The Armageddon Game #1 (by Tom Waltz, Vincenzo Federici, Matt Herms, and Shawn Lee) finds the eponymous heroes, now under the leadership of Oroku Saki himself, come together with none other than the maniacal Karai in the hopes of uniting with the Foot Clan as the Armageddon Game looms ominously overhead. While the two factions are able to come to an agreement, theirs is hardly the only surprising partnership that has been made recently. The Rat King, who has already allied himself with Madame Knull, Baxter Stockman, and the interdimensional Krang, has also found in Doctor Jasper Barlow the kind of ally who can destroy his enemies without ever coming into contact with them.
Thanks to having previously experimented on Donatello, Doctor Barlow is able to provide the other villains with samples of the hero's mutant DNA. Presumably, it was Null Corporation who subsequently created their own clones of the Turtles, while it was the Rat King who ensured they would launch a full-scale assault on Mayor Stockman. In spite of all Stockman's past crimes, he is still the moderately to begrudgingly beloved mayor of New York City, while the real Turtles genuinely can't afford to lose much more of their reputation than they already have.
During a press conference, Mayor Stockman is attacked by four mutant Turtles who, to the trained eye at least, are clearly not those belonging to the Splinter Clan. Unfortunately, there doesn't seem to be anyone at the event who is capable of recognizing these imposters for what they are, especially thanks to them each carrying one of the real Turtles' iconic weapons. By the time their direct assault is over, Stockman is being held hostage as part of an increasingly dangerous standoff. It is more than obvious that the people who will be harmed the most by the entire situation are the ones who were never there, to begin with.
Unlike the massive, hulking Slash or even the lanky Punk Frogs, there is no immediate way to tell that these imposter Turtles aren't actually the Splinter Clan has gone rogue, which makes them more dangerous than almost any other enemy. Not only are they a capable threat in their own right, but these new Turtles are also already establishing the originals as violent antagonists towards the human regime, if not outright villains. With that, it won't be long before the people of the city begin turning on their mutant protectors, nor before they cheer on Stockman's next anti-mutant crusade.
Assuming Stockman's resources have expanded since aligning himself with Null, Krang, and the Rat King, it is hard to imagine anything stopping him once he gives the order for the Turtles to be eradicated. With public opinion on his side, there wouldn't be anyone standing in his way, and with more than one army under his relative command, those that might would fall in an instant. With any luck, someone will be able to lift the veil from these new Turtles' faces, otherwise they might just be the only ones left before the Armageddon Game is finished.