The Villains: Kang the Conqueror and Doctor Doom
Two of the most powerful villains of all time struck a deal. Doctor Doom promised to enhance Kang's time ship so that it could not only travel across time, but across dimensions as well. They two villains would then conquer any dimensions that suited them. In return for his help, Kang would let Doom keep the first dimension they conquered all to himself. So the two overlords used Kang's time ship to open a portal to the dimension known as Middle Earth.
Unbeknownst to Kang or Doctor Doom, The Avengers had been tracking Kang and Doom for weeks, and they decided to attack just as Kang and Doctor Doom crossed over into Middle Earth.
Team 1: The Avengers (Iron Man, Captain America, Hulk, Thor, Black Widow, Hawkeye, Scarlet Witch, Quicksilver, Vision, Ant-Man)
As the Avengers crossed over into Middle Earth, they latched onto Kang's time ship and started to tear it apart. But Kang and Doom ejected from the ship, along with a small army of Doombots. Doom and Kang flew for miles and miles, until they stumbled an eclectic group of warriors.
Team 2: The Fellowship (Aragorn, Frodo, Sam, Gandalf, Legolas, Marry, Pippen, Gimli, Boromir)
Kang and Doom attacked the Fellowship, and the battle raged on for several hours. Finally, after neither side gaining the upper hand, Doctor Doom grabbed Frodo and fled along with Kang and their remaining Doombots.
Shortly after, The Avengers showed up, having tracked Doom and Kang to the Fellowship. The two teams agreed to team up to defeat this new threat, and they set off in search of the ellusive villains. As they set off, Hawkeye and Legolas tried to convince the other that he himself was the superior archer.
Doctor Doom and Kang brought Frodo to a cave deep in a mountain and torchered him until he told them why he and The Fellowship were traveling to Mordor. He gave up the ring to them, and Kang tried to put on the ring. But Doom knew the ring must be destroyed, that it would serve no master other than Sauron. So he took the ring from Kang and left for Mordor, determined to throw the ring into Mount Doom. Kang, in frustration, cast Frodo down the mountain, then chased after Doom. Frodo landed on a small ledge far down the mountain, but he still lived.
Doctor Doom flew into Mordor, and without much resistance cast the Ring of Power into Mount Doom.
Sauron was defeated. Kang arrived soon after, and, coming to his senses, joined Doom again. The remaining armies of Sauron swore fealty to Doom and Kang, and Doctor Doom outfitted them with advanced armor scavenged from his Doombots.
Not long after, The Avengers and The Fellowship tracked Doom and Kang to the cave that they had interrogated Frodo in. They found Frodo and the side of the mountain, barely alive. Gandalf and Scarlet Witch used their combined skills to heal Frodo, and he told the group how he has told Doom and Kang everything, as well as gave up the ring. The Avengers and The Fellowship immediately set out for Mordor, arriving several hours later thanks to Iron Man, Quicksilver, The Hulk, Thor, and Vision.
As soon as the heroes arrived, Doom's orcs attacked. A brutal and bloody battle ensued. The Fellowship had a hard time fighting the advanced technology Doctor Doom supplied the Orcs, but the Avengers took them on easily. The heroes had dead water nearly half the Orc army, but then Doom and Kang entered the battle. Doom had upgraded his and Kang's armor with dark magic.
Last Team Standing: The Fellowship
Scarlet Witch tried to nutrulaize the magic in Kang's armor, but Doctor Doom attacked her with a spell too powerful for her to withstand. Her heart stopped from the strain of trying to deflect the spell and died. Gandalf blaster Doom with a spell of his own, but Kang attacked from the side and broke Gandalf's staff. Emboldened by their leaders, the Orc army advanced with even more ferocity than before. Quicksilver and Black Widow were soon overwhelmed and struck down. Hawkeye fought side-by-side with Legolas, and when he ran out of arrows Legolas have him one of his swords to defend himself. Captain America attempted to take on Doom, but he was quickly cornered and Doom shot him to death. Ant-Man tried to climb into Kang's ear, but Kang omited a concussive blast from his armor and knocked Ant-Man right into an orc's grip, who squished him. Finally, Iron Man came up with a plan. He set his armor for self-destruct, then flew right at Doctor Doom and Kang. His armor exploded, killing Tony but stunning Kang and Doctor Doom. As fast as lightning, Thor and Vision grabbed Kang and Doom and flew them right into the lava of Mount Doom, not letting go for an instant. Vision, Thor, Doctor Doom, and Kang all melted into the magma of the volcano.
Seeing their leaders defeated, the Orc army turned and fled back into Mordor, the Fellowship, Hawkeye, and Hulk chasing them all the way. Finally, all the Orcs were cornered, and Hulk finished them all off. When every last Orc was defeated, Hulk collapsed, poisened by the hundreds of Morgul blades and arrow tips piercing his tough hide. The Fellowship brought Hulk to Rivendale as fast as they could, but by then it was too late. Hawkeye was the only remaining Avenger. Only the Fellowship had survived the battle.
The only one of the Fellowship who had perished was Pippen. After the great evil was defeated, The Fellowship went their separate ways. Hawkeye went with Legolas to the woodland realm, never able to return to his own world. He was adopted into the Elven culture, and became a respected warrior in their society.
And there was peace in Middle-Earth for the rest of their lives.