Squirrel Girl is originally from the Los Angeles, California area. She was first seen ambushing Iron Man in a forest. She hoped to impress the veteran hero, wishing him to take her under his wing as his sidekick. The 14 year old mutant introduced herself and her pet squirrel Monkey Joe, and displayed her various abilities (all of which were Squirrel themed). Unimpressed, Iron Man politely declined, when suddenly the duo was attacked by Dr. Doom in a large aircraft. Doom captured and subdued Iron Man, and began to fly out over the ocean where he planned to dispose of Iron Man's body once he killed him. Underestimating her, Doom left Squirrel Girl to her own devices. She devised a plan, and used her ability to communicate with squirrels through an open door as the ship passed over the forest. Hundreds of squirrels answered her call and flooded Doom's ship, chewing through the wires, and swamping the evil dictator with their furry bodies, causing Doom to exclaim "Confound these wretched rodents! For every one I fling away, a dozen more vex me!" Iron Man was freed, the duo emerged victorious, and the two heroes went their separate ways. Squirrel Girl was next seen years later, having relocated to New York City for what was acknowledged in the comic as no clear reason. While fighting crime in Central Park, she encountered Flatman and Doorman, members of the Great Lakes Avengers on a membership drive. In addition to appearing in the G.L.A. miniseries starting with the second issue, Squirrel Girl introduced each issue, providing a disclaimer or opinion piece about the contents of the series. Her side-kick Monkey Joe was also added to the team (at Squirrel Girl's behest), and commented on the series as well, appearing in a circle at certain moments in order to make comedic and smart-aleck remarks. After Squirrel Girl ensured that Monkey Joe was made an official member of the GLA, he was killed by an assailant dressed as Dr. Doom, who had come seeking revenge. In actuality, his killer was a rejected member of the GLA named Leather Boy, who had been dressed in a variation of Dr. Doom's costume. Enraged by the death of her friend, Squirrel Girl was able to help stop Maelstrom from destroying the world by assembling a squirrel army. Squirrel Girl found a new squirrel companion during this battle — the only one of her squirrel army who had survived Maelstrom's wrath, whom she named Tippy-Toe. Squirrel Girl and Tippy-Toe later managed to defeat M.O.D.O.K., Terrax and Thanos all by themselves. Uatu, the Earth's Watcher, was on hand to confirm that the Thanos she defeated was the real thing, and not a clone or copy of any kind (an explanation that has sometimes been used to excuse some of Thanos' more embarrassing performances over the years). After M.O.D.O.K. was defeated, Dum-Dum Dugan offered her a position at S.H.I.E.L.D., explaining that they had been watching her for some time, impressed by her effectiveness in defeating powerful supervillains. Dugan's computer screen showed her taking on Mandarin, Doctor Doom, and Giganto, each presumably some time in the past. Squirrel Girl declined the offer, saying she was happy being with the GLA. She is a huge fan of the New Warriors, especially Speedball, on whom she has a crush.it was revealed that all of the Great Lakes Champions (the new name change came about as the result of a poker game) had registered under the Superhuman Registration Act the morning it was announced. Squirrel Girl recently bested Deadpool in combat after he had defeated the rest of the team. Ironically, Deadpool failed to recognize Squirrel Girl, even though he owns Squirrel Girl-themed underwear. By this time the team had changed names again, to the Great Lakes Initiative as part of the 50-State Initiative. Shortly after this, Deadpool showed her the Stamford incident, Whereupon she tried to convince Robbie to return to being speedball. His insane insistance on his Angst drove her nuts. She then flew to Latervia, wher Doc Doom allowed her the use of a time Machine. She teravelled briefly to 2099, but failed to again convince Speedball to return. She returned to the present and kicked Deadpool out of the GLI's Headquarters. It is rumored that during the recent Skrull war, Squirrel Girl was off defeating Galactus. Squirrel Girl, as a character, "doesn't like Superhero stories where everyone is all dark and moody"—and has a slightly naive, why-isn't-this-the-silver-age attitude towards those she meets. In spite of her lot in life (constant teasing in school, for instance, and the fact no one outside her own team takes her seriously) she's probably the most well-adjusted Marvel Mutant in history. She should harken back to the days when Comics were just fun stories for kids. "I prefered it when comics were a world you wanted to escape to, not escape from." "Its Squirrel Girl, you Evil, Evil Man!" (to Deadpool after he blew up the GLI HQ) Squirrel Girl is a mutant, and evinces a variety of mutations which align with the squirrel theme. During her first encounter with Iron Man, she provided a detailed demonstration of her powers and abilities: a furry, prehensile tail roughly 3-4 feet in length; sizable buck teeth, which are strong enough to chew through wood; enhanced agility and strength, enabling her to jump between trees with ease. Her fingers have sharp claws on them, assisting her with climbing, and she possesses retractable "knuckle spikes" roughly 2-3 inches in length on each hand. Most importantly, she is capable of communicating with and understanding squirrels. Squirrel Girl does not communicate with squirrels telepathically. Rather, she has an understanding of their language, and the ability to speak it. Squirrels have also been depicted as understanding her when she speaks in English. Whether this power extends to species of ground squirrels and other rodents, or is limited to the traditional tree squirrel is presently unknown. Later appearances have revealed additional abilities possessed by Squirrel Girl. Her eyes have been seen to glow red in low-light situations, indicating that she has some form of enhanced vision. Squirrel Girl reveals that her lips taste like hazelnuts, and she also displays an enhanced sense of smell. Squirrel Girl carries a utility belt comprised of multiple pouches which contain nuts to give as snacks to her squirrel friends. These are known, to much comedic effect, as her "nut sacks". It is unknown whether the markings around her eyes are the result of her mutation, or are cosmetically applied to enhance her squirrel-themed appearance. Squirrel Girl is also shown as carrying a full set of 'Iron Man VS Series battle cards' when showing Dum-Dum Dugan how she knows him. (She mentions Dugan has a 'defense stat of 8'; her own is 6, although the rating system is left unclear.) After M.O.D.O.K. is pointed out to her, she consults the supervillain's own card to confirm his abilities. The printing on the two cards shown (Dugan's and M.O.D.O.K.'s) is actually gibberish. (She's not the only member of the team so equipped: Mr. Immortal has a complete set of X-Men cards as well) Squirrel Girl is always accompanied by one or more squirrels. Two of these, Monkey Joe and his successor Tippy-Toe, are her constant companions. At her insistence, they have both been accepted as full members of the Great Lakes Avengers. Squirrel Girl stands at a slightly-below average height (probably 5'3" to 5'5" or so, though its never specifically stated) Her most obviouys feature is the gigantic squirrel tail, and she also has buck teeth. She wears a black bodysuit that covers her from neck to toe, covering her entire body, including her hands and feet. Over this she wears a brown, furry tank top and bikini, along with fur-covered leggings and forearm bands, that reach from her angle to just below her knees and from her wrists to just below her elbows. Black boots and her utility belt filled with nuts complete the outfit. She has curly, reddish-brown hair, worn short, and seems perpetually happy.

Find Weakness is how Squirrel Girl tends to 'Punch above her weight class'—defeating cosmic-level villians: defeating Modok by throwing Tippy Toe where his weapons couldn't reach, defeating Bi-Beast by smell, defeating Deadpool by bleeding injuries too small for his healing factor to kick in, and so on.