While the rest of the X-Men and Avengers, aided by the Shi'ar Empire were holding off the forces of the alien menace the Gr'ey, an unlooked for explosion blew in a section of the cavern.
Iron Man seeing his chance swung by and grabbed two of the nearest heroes to him, Captain America and Cyclops and headed into the breach.
Three squads of the Shi'ar Alien Legion followed them before the Gr'ey managed to cause an avalanche sealing the party in.
The entrance of the party detected by the alien menace who made this hollowed out mountain in South America their base.
Two full squads of the Gr'ey ordered forward their enslaved Brood minions. The alien leader, Aria Fif Teone, led the pack but along side him was his earth created collaborator the android Ultron!
The Brood troops moved quickly towards the enemy, their powerful will subject to the subtle mental energy of the Gr'ey.
Gun fire echoed down the tunnel walls as the Gr'ey fed slave squad after slave squad into the advancing Alien Legion and their human allies.
Captain America led the charge in the opposite direction and one well placed shield toss left a Brood warrior out of the fight.
Iron Man followed a different path with a squad of the Alien Legion and engaged the huge doomsday device that was now being raised to the surface. Two enemy Brood squads engaged them but the assault rifle fire of the Legion and Iron Man's repulsor rays made short work of them.
His enhanced senses showed Captain America about to leap into the fray with a bunch of Brood when one of the Gr'ey pointed a beamer at him and the First Avenger quickly plummeted to the earth. Iron man could see his friend straining every muscle to get up but to no effect.
He fired his boot rockets and flew among the Gr'ey. He was so close that they couldn't bring their weapons to bear against him.
His fists, however, told among their numbers and soon the Gr'ey were around him unconscious while the last one of them fled.
He turned his repulsor rays on the massive pieces of equipment powering the defenses of the mountain. He could hear the Legionnaires behind him bringing down the doomsday device with a storm of fire from their various weapons.
Ultron chose this moment to strike and flew among one of the squads of Legionnaires, his adamantium fists pushed forward by the mechanical servos flattening soldier after soldier. They clubbed their assault rifles but that had little effect on the all but indestructible android.
Cyclops blasted away an entire squad of Brood that were coming to support Ultron, but as the last of the Gr'ey Iron Man had tangled with fled past him he turned and fired his gravity beamer at the X-man, who succumbed to the increased gravity inflicted on him and sunk, helpless, to the ground as Captain America had done before him.
The other two squads of Legionnaires spent time wrecking the machinery in the caverns and then a familiar sight momentarily disrupted the fighting between the man of iron and the man of adamantium, the hammer of Thor raced down the cavern. With their defenses down the Gr'ey could no longer keep the rest of earth's defenders at baby.
Ultron smashed Iron Man in the face and flew away. He dreams of conquest and death defeated, he would return to menace the Avengers anew.
But later.
comes up with a roster and game stats for the Wildcats, his mercenary force.