In this new spinoff series from the Avengers: Earth's Mightiest Heroes saga, the Avengers are accidentally transported to the Digital World, where they are greeted by strange creatures called Digimon, who instantly change into magic armors and bond with the Avengers, much to their displeasure. They soon find out, though, that Loki has escaped from the Midgard Serpent and has joined up with the monstrous overlord, Surtur, as his emissiary. Not only that, but he's also gathered an entire army of villains from Prison 42 and evil Digimon from the Digital World in order to conquer both worlds: The Real World and Digital World. Can the Avengers stop Loki and Surtur's evil schemes with their newfound Digimon Spirit powers in time?
The Avengers' Digimon Spirit Armors were specifically chosen by Odin to team up with them based on their characteristics and virtues.
- Iron Man (Nolan North) - Warrior of Courage, the leader of the Avengers. As with other incarnations, Tony is a former weapons manufacturer who became a superhero after a crippling incident that both damaged his heart and led to his becoming "The Invincible Iron Man." After the break out at the various super-villain prisons, he urges the collected heroes to join forces as The Avengers, providing them with their headquarters as well as leading the team itself. His spirit is Agunimon.
- Captain America (Brian Bloom) - Guardian of Friendship. Originally a frail, sickly young man, Steve Rogers was selected to become the first recipient of Abraham Erskine's super soldier formula. Forever transformed, he became the legendary Captain America, hero of World War II. Thought killed in battle with the Red Skull, Steve was actually frozen in ice, until he was discovered and revived by the Avengers. Now, he fights to avenge wrongs in the modern day. His spirit is Lobomon.
- Thor (Rick D. Wasserman) - Storm of Reliability. Thor has grown tired of the endless wars of Asgard, and believes that by acting as a hero on Earth, he can make more of a difference. This creates a conflict, in that his fellow gods desire for him to return to Asgard so that he may help defend it whilst their father, Odin, sleeps to replenish his powers. His spirit is Korikakkumon
- The Hulk (John DiMaggo) - Berserker of Sincerity. Mutated by exposure to Gamma Radiation, Bruce Banner developed an alternate personality that manifested as the rampaging monster known as The Hulk. However, Banner and Hulk have made peace with one another, and are set on proving their worth to the world while also seeking to undo the damage done by other beings harmed by gamma radiation. His spirit is Gigasmon.
- Yellowjacket (Wally Wingert) - The Scientist of Knowledge. A scientist who developed both the ability to shrink or grow larger, as well as communicate with insects, Hank Pym has also developed numerous advances in a variety of fields. He's just as interested in rehabilitating the villains the Avengers battle as he is in stopping them, believing that many of their enemies are sick people in need of help. His spirit is Beetlemon.
- Wasp (Grey DeLisle) - The Aerial Ace of Love. Hank Pym's girlfriend and financial benefactor. She also has powers, and unlike Hank, believes that she and Hank can both make a difference as superheroes, which prompts her to take up arms and join the fight when super-villains come calling. Her spirit is Kazemon.
- Hawkeye (Thomas F. Wilson) - The Archer of Hope. An elite agent for SHIELD, who worked with the Black Widow against high level threats like The Hulk, until Widow framed him as a double agent for HYDRA. Clint then became incarcerated in the Vault, but then set free during the breakout event. He soon managed to clear his name. Refusing to work with the SHIELD agents who doubted his innocence, he joined The Avengers in hopes of locating the Black Widow. His spirit is Sagittarimon.
- Ms. Marvel (April Stewart) - The Seeker of Light. A friend of Wasp's who does research for the military. After Philip Lawson, aka Captain Mar-Vell, shields her from a Kree sentry's attack one night, she develops superpowers. She joins the Avengers in the midst of Kree invasions. Carol also works as an agent for SWORD, the division of SHIELD that tackles extraterrestrial threats. Her spirit is Mermaimon.
- Captain Mar-Vell (Roger Rose) - The Champion of Shadow. A Kree alien scientist stationed on Earth. His stay caused him to develop an appreciation for the planet, particularly a fondness for Carol Danvers. This has motivated him to try and convince the other Kree aliens that Earth could prove a valuable asset in the Kree/Skrull war. However, this leads him into becoming corrupted by Loki into becoming the Dark Warriors's agent, Duskmon, until he is freed from their control by Ms. Marvel, and is upgraded into the spirit of Loewemon.
The Dark Warriors
Led by Loki, the Dark Warriors serve as Surtur's champions of darkness within the Digital World. They are composed of evil super-villains that are the direct adversaries to each of the Avengers.
- Surtur (John DiMaggio) - The Ultimate Evil. Surtur's wrath at being trapped in Muspelheim for thousands of years has reached its focal point, and now he has broken himself out to lead the invasion on the Digital World and the 9 realms of Asgard which surround it. His demon spirit is GranDracmon.
- Loki (Larry Cedar) - The Trickster of Pride. Thor's step-brother and an enemy of Asgard. He conspired to wage war on his fellow gods by recruiting the Frost Giants, but they were defeated, and Loki was sent to the Isle of Silence, where he would remain imprisoned. But this was just part of his plan, as he immediately broke out and took over Asgard and the other 9 realms while Thor was away. Although the evil god was defeated in the end, he was freed once more by the dark demon Surtur to attack the Digital World with the other 6 dark warriors. His demon spirit is that of Lucemon.
- Obadiah Stane (Clancy Brown) - The Businessman of Greed. The CEO of Stark Industries, taking over after his friend Howard Stark died. His friendly image hides an amoral and sinister mind who seeks to use the Iron Man armor for his own ends. His demon spirit is Barbamon.
- Red Skull (Clancy Brown) - The Warmonger of Wrath. The opposite number and greatest enemy of Captain America. A super soldier created by HYDRA, he sought to attain the power of the Asgardian beings before his schemes were stopped by Captain America and his sidekick, Bucky. Unfortunately, he lived on to survive another day, while Captain America lost his closest friend and plunged into the icy arctic waters. In the present day, he has disguised himself as the US Secretary of Defense, and manipulated Winter Soldier, General Ross and Doctor Samson to work for him. His demon spirit is Daemon.
- The Leader (Matthew Frewer) - The Genius of Envy. A Diabolical Mastermind, The Leader organized much of the prisoners of The Cube to act as a distraction before he completed his plan to turn the whole world into gamma monsters under his mental control. Arrogant and Proud, he was soundly defeated by Thor, Hawkeye and Hulk working together. His demon spirit is Leviamon
- Amora the Enchantress (Gabrielle Carteris) - The Sorceress of Lust. An Asgardian sorceress who uses black magic to manipulate others. She acts in service to Loki, and her faithful servant is the axe-wielding Executioner. She is also desperately in love with Thor, but he rejects her, thus her motivation for killing him. Her demon spirit is Lilithmon.
- Ultron (James Horan) - The Robot of Sloth. Originally designed by Hank Pym as jailers for the Big House prison, Ultron was supposed to be humanity's only hope for world peace. But when his system was reprogrammed to understand violence in order to help fight Kang's invasion, Ultron became self-aware and decided to follow his programming to whatever logical step came next. This happened to be eliminating the entire human race, which he saw as irredeemably flawed and thus the cause of all the world's chaos. His demon spirit is Belphemon.
- Doctor Doom (Clive Revill) - The Overlord of Gluttony. The ruler of Latveria and the arch-enemy of the Fantastic Four. Proud and Arrogant, Doom is nonetheless an intelligent schemer with clear goals in his dual quests to rule the world and prove his intelligence greater than Reed Richards, and has the technology and skills to help back up his claims. He often buys goods to increase the power of his robot army, and even sent the Baxter Building into space one time. His demon spirit is Beelzemon
- Veranke (Elizabeth Daily) - The Seeker of Darkness. The Queen of the Skrull Empire and leader of the Secret Invasion. SHIELD Agent Barbara Morse (aka Mockingbird) was captured by the Skrulls and Veranke replaced her, thus getting in closer to manipulate her enemies directly. Her demon spirit is MaloMyotismon.
The Monsters of the Week
Because the Avengers and their Digimon partners are getting closer and closer towards defeating the Dark Warriors, Surtur has unleashed an entire army of villains from Prison 42, and has given them digital powers to make them more fearsome and powerful than before.
- The Wrecker (John DiMaggio) - Leader of the Wrecking Crew, he was the first super-villain to confront the DigiAvengers, having been sent by his masters, Loki and Leader, to attack them right after they landed in the Digital World. Thor eventually defeated him and scanned his fractal code. His special attack is Crowbar Guillotine.
- Absorbing Man (Rich D. Wasserman) - A victim of Gamma Radiation, "Crusher" Creel, aka the Absorbing Man, gained the ability to absorb the properties of whatever he touched. He's one of the few in-mates to ever escape from the "Gamma Research Facility" The Cube, but trying to take on The Hulk ended up putting him right back in there. That is, until Loki broke him out again and gave him the powers of water to make him more powerful. He was eventually defeated by a dual attack from Thor and the Hulk, and had his fractal code scanned by Thor. His special attack is Copy Touch.
- Thunderbolt Ross/Red Hulk (Keith Ferguson/John DiMaggio) - Thunderbolt Ross leads the Hulkbusters, who have pursued the Incredible Hulk for years, but never managed to capture him. SHIELD ultimately beat him to capturing the monster, although he later escaped. The Winter Soldier, under Red Skull's orders, eventually helped Ross obtain a sample of Hulk blood, which turned Ross into a new gamma monster, the Red Hulk. With the power of a Hulk at his disposal, Ross attacked the DigiAvengers until he was defeated by the true Hulk and got his fractal code scanned by the not-so-jolly green giant, ending his long war on Hulk forever. His special attack is Burning Fist.
- Kang the Conquerer (Jonathan Adams) - Ruler of Earth in the 41st century, the time-traveling conqueror Kang was pleased with his domain until it began breaking apart and disappearing from reality. Through watching the past, he deduced that the cause of this had something to do with Captain America, and he transported himself and his entire fleet of warships back in time in order to confront the Avengers and conquer their time period. It is later revealed that Kang's timeline disappeared because of Ronan and the Kree destroying the sun, which leads to Captain America letting Black Panther live instead of dying to stop the sun from blowing up. His special attack is Chrono Breaker.
- Ulysses Klaw (Mark Hamill) - A scientist who desires to study and manipulate Vibranium, Ulysses Klaw first attempted to steal a sample of Vibranium from Hank Pym. He was defeated and allied himself with M'Baku the Man-Ape, in order to gain control of Wakanda's Vibranium. He helped M'Baku assassinate T'Challa and later attempted to sell his weaponry to HYDRA, only for the Avengers to attack his mining operation. Klaw was knocked into some unstable Vibranium, and turned into a living concentration of sound focused around his own sonic weapon. He was ultimately defeated when Ant Man and Iron Man trapped his weapon inside of a hollowed out piece of Vibranium, then blew him up, leaving Ant Man to scan Klaw's fractal code and return him to normal. When he transforms himself into his sound form, his special attack is Lightning Blade.
- Whirlwind (John Kassir) - A super-villain hired by Klaw to steal sonic weapons research, Whirlwind was confronted by the Wasp and Ant-Man. Once defeated, he found himself in the Big House, and when the breakout occurred, he vowed vengeance on the two who had beaten him - the Wasp in particular. His special attack is Hurricane Gale.
- Man Ape (John DiMaggio) - A survivor of the White Gorilla tribe, M'Baku conspired with Klaw to usurp the throne of Wakanda. M'Baku challenged T'Chaka, the original Black Panther, to ritual combat, and had Klaw use his sonic weapon to disorient him long enough for M'Baku to deliver the killing blow. He then became king and attempted to purge Wakanda of Vibranium and modern influences in order to return the country to its old ways. He was slain and had his fractal code digitized by Black Panther, who regained power and turned leadership over to a council. Eventually, Loki resurrected Man Ape and gathered him and several other villains to form the Lethal Legion. His special attack is Mega Bone Stick.
- Malekith (Quniton Flynn) - A powerful sorcerer and ruler of the extinct race of Dark Elves, Malekith was employed by Loki to obtain the Casket of Ancient Winters from its hiding place in Norway to further the trickster's own schemes. When the Enchantress and Skurge came to collect, however, Malekith decided that the Casket would be put to much better use in his own hands and used its powers to freeze them where they stood; he then unleashed the artifact's power, encasing the world in a sudden ice age in order to turn it into a paradise for the souls of his Dark Elf followers. He proved a formidable opponent for Thor, Iron Man and Black Panther, but in the end he was slain, had his fractal code digitized by Thor, and the Casket was closed, putting an end to Malekith's megalomaniacal desires. His special attack was Subzero Ice Punch.
- MODOC (Wally Wingert)- MODOC is the leader of A.I.M., better known as the Advanced Idea Mechanics, a group of arms-dealing scientists for hire. Transformed into a cyborg with a nightmarish large head and mental powers, MODOC sees himself as the "ultimate man-machine interface", though many are simply disturbed by his strange appearance. His special attack is Solar Ray.
- Grim Reaper (Lance Henriksen) - A criminal who became a HYDRA agent in order to satisfy his destructive impulses. He infiltrates The Vault in order to free Baron Strucker, but ends up being captured for his trouble. Despite his defeat, he's a deadly threat, and a skilled assassin. His arm is a cybernetic implant that transforms into a scythe. His brother is Simon Williams, who he introduced to A.I.M., resulting in his transformation into "Wonder Man." His special attack is Zombie Claw.
- Odin (Clancy Brown)
- Nick Fury (Khary Payton)