With the announcement of a new "Weapon X" ongoing series coming in 2017, one has to wonder what aspects of the long-running government agency will make their way into the new comic. The teaser art released with the announcement included images from the program's storied history and many of its deadliest alum -- but there was one character noticeably absent. That character...is Weapon II.

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Yes, the "X" in Weapon X isn't a letter; it's actually a Roman numeral. And yes, that means there were many test subjects before the tenth one (Wolverine) was weaponized. The second Weapon just so happens to have a connection to...Squirrel Girl.

First, the whole "'X' isn't a letter" thing started back in 2002's "New X-Men" #129. In that issue, writer Grant Morrison introduced Weapon XIII -- a.k.a. Fantomex. And he did the honors of dropping that Weapon X truth bomb.

It was later confirmed that the first of many weapons created by Weapon Plus was Captain America. Later experiments were conducted on everything from criminals to animals, all before Weapon X shifted focus to mutants (and, eventually, Wolverine). Fourteen years after this initial revelation, the "Animal House" crossover between "Unbeatable Squirrel Girl" and "Howard the Duck" finally showed readers the menacing results of those early Weapon Plus experiments: Weapon II.

Actually, Weapon II appeared in an unnamed cameo -- above -- in late 2015's "Howard the Duck" #1. And then, a few months later, readers got to really meet the little berserker.

"Unbeatable Squirrel Girl" #6 kicks off the two-parter with the private eye Howard the Duck approaching Squirrel Girl for help tracking down a missing cat named Biggs. Their investigation led them to a big mansion located on a private wildlife preserve hundreds of miles outside of New York City. It's there that the eccentric billionaire Ms. Shannon Sugarbaker planned to fulfill her horrific lifelong dream of hunting people. But since she couldn't legally hunt people, she figured that anthropomorphic animals would be the next best thing.

Ms. Sugarbaker introduced the captive Howard to her prey: Rocket Raccoon, Beast, the newly cybernetic Biggs (he once belonged to Sugarbaker's ex). And yep, Weapon II -- a highly intelligent squirrel with an adamantium skeleton and claws, and also a healing factor.

Sugarbaker kicked off the hunt by dropping the ragtag band of animal and animal-themed heroes off in the forest. She then began hunting them with her deadly accurate cosplay accessories. With the hunt launched, Weapon II jumped into the fray!

But not even the pint-sized warrior's deadly skills could overcome Sugarbaker's deadly costume.

With all the rest of the heroes captured, Howard and Squirrel Girl teamed up, suited up in Sugarbaker's leftover super-accessories, and came to the rescue. While Howard tussled with the maniacal millionaire, Squirrel Girl freed Weapon II -- who totally cut loose after being cut loose!

Ms. Sugarbaker was soon defeated, and Biggs became Howard the Duck's pet cat. We've yet to see Weapon II in the months following the "Animal House" adventure, and it's probably a safe bet that he won't pop up in the upcoming "Weapon X" ongoing. Still, it's fascinating to see how a passing mention in a Grant Morrison comic turned into a full-fledged -- and fully adorable -- character in a storyarc published just this year.

And you never know, maybe Weapon II will return soon. You just can't keep a adamantium-clawed squirrel down. Or at least you shouldn't. Weapon II doesn't mess around.

Marvel's new "Weapon X" ongoing launches in spring 2017.