An apology: When I wrote this chapter a while ago, I didn't suspect that the Tesseract was an Infinity stone. In this plot, the "warm light for all menkind to share" isn't the mind gem. It is an original-story-twist on my side, but the cube has been my idea of the Bifrost's restoration from the beginning of this story, two years ago.
Why Killing the Fun
The Infinity Gems, as delightfully helpful as they were, showed Thanos the coming of the Avengers. Irritated, the titan sent a destructive wave of energy towards the rainbow tube. When he saw that Heimdall had managed to gain control over the teleportation, Thanos was even more delighted - someone was posing a challenge. He loved that.
The Bifrost produced a ray of light for the Midgardians and the two Asgardians to come through. Explosions could be heard in the distance. Earth's heroes had already started going out the Bifrost only to see that all hell had broken loose above the Shining City. Large ships were hovering in the air, casting ugly shadows to the attacked land. Smaller ships were raging and sending their fire down where Asgardian weapons and warriors from different worlds fired back.
"Thanos," was the only thing the younger god said. But where was he now? The feeling of dread started crawling up Loki's spine, but he heard Thor's angry promise. "He will pay for that!" This helped the Trickster regain some of his composure. Thor looked at his brother, whirled his hammer and charged into battle. This left no trace of fear in Loki's heart. Now there was only the fight ahead. He teleported into the palace, leaving the Midgardians to form their attacking groups with people who would attack from air and those who would fight on ground.
The hordes of attackers noticed the coming reinforcement. A command was given and some of the attacking smaller ships turned towards them. There was no mercy from both sides, but Asgard started taking prevail over the enemy. Flying black jets exploded never to fire a single laser of destruction again. Chitauri and Space Pirates were scattered to the point of retreating. Somewhere could be heard exclamations of victory. Tony Stark turned towards the happy noise and quirked an eyebrow. Was it that easy and quick to win that war? What was all the fuss about then? Asgardian space ships prepared to chase the intruders when a deafening thunder was heard. Even the ground shook with it.
Loki stopped in his run through the palace to listen, but the demi-god didn't have the time to wait and see what else was coming towards Asgard, for he was attacked from Space Pirates. After he cleansed another royal corridor of intruders he resumed his run towards his quarters. A strange force field was preventing him from teleporting inside the palace, nor did he could call out the book he needed – a book he never dared open. This volume could bring victory or ruin. He only had to wait until the right moment to challenge Thanos, so the titan wouldn't suspect his plan.
After the thunder left its echo, every soldier went quiet with anticipation. Somewhere a very purple wicked grin widened even more. "Let's see how they will deal with three armies more." Portals all over Asgard opened to let armies of Frostgiants and Dark Elves. The Jötuns had gained their grip on the Casket of Ancient Winters. They attacked the fire beings of Muspelheim and turned them into ice. Seconds after the two armies came, a third one emerged from the portals - twisted dark creatures leaded by Hella.
Loki frowned. Was that Fenrir running besides his daughter? He had managed to exit the palace, having the dangerous book safely tucked under his armor. Seeing the god of Mischief the great wolf ran towards him. Loki could clearly see the flash of deadly fire in the eyes of his son and the white dripping with saliva fangs. For a moment everything seemed to move in a cadence. Loki could hear no cry of attack, stomping of heavy giant's steps on the ground, or the rumble of explosions. All he could hear, or see was Fenrir coming closer. A single tear rolled down Loki's cheek. They should have fought on one side. Now it was son against father. When Fenrir was close enough the wolf jumped forward. Loki didn't want to hurt him, so he only ducked, knowing that eventually someone will get injured in this fight. But the moment his son landed behind him, Loki heard roar and the scream of somebody dying. When he turned to look he was met with the muzzle of the great wolf. His fangs were still holding the torn out windpipe of the Vanir he had just stopped from attacking his father from behind. Fenrir dropped it in Loki's feet, gave him one last look and ran towards a bunch of the ugliest creatures Loki had ever seen, Hella's soldiers. The creatures ran in screams as they saw the wolf attacking them. The Trickster smirked. "One came to fight for Asgard and one came to destroy it. I could be proud with both of them."
When Thanos saw that Fenrir didn't fulfill his purpose the titan cursed. He wanted to force Loki into willingly killing his own son, but the Soul gem didn't have power over the hellish creature. Thanos thought that Hella had convinced the wolf to fight alongside her. What had gone wrong? "Useless creature!" With that Fenrir's heart bust inside him. His eyes rolled in his head and the great beast fell to the ground. But Loki didn't see that. He was far away, surrounded by a group of Frost Giants. He fought them with unearthly grace. He was leaping and dancing, delivering deadly blows to the nearest ones. Still, the giants were too much, and they tightened their deadly circle around him with every second.
The Chitauri and the Space Pirates had come back. Another army of extraterrestrial little blue creatures with pointy ears was added in the list of enemies. What seemed like massive black zombies with hooded heads, and with not two but five glowing red eyes emerged from the ground and threw themselves in the fight against Asgard.
Thor wielded his hammer with great power, but the flow of the enemy seemed to never end. The warriors three and Sif already had injuries each, but they kept fighting with all their might, slaying their foes as they dared come near. Stark flew up, trying to shake off several little blue creatures which had started melting his Iron Man suit with acid teeth. The moment he was rid of them he took a look at the devastation of the Shining City. "So much for winning." It had to sound like a joke, but it came with an unintended defeat in the intonation. A flying jet with Chitauri almost collided with him, but Tony escaped the hit only to crush into another jet.
Thanos stood in his own spaceship overlooking the battle scene. It pleasured him - all these fighting skills, the leaders in action - scheming and planning the next step of their army, the heroic struggle for overpowering the enemy. It all was such a fun to observe. He didn't mind nations destroying each other. With, or without his intervention he was going to have the throne of Asgard soon enough. And with that all other worlds in the universe would fall. He grinned as he watched the Frost giants attack the magicians of Muspelheim with the Casket of ancient winters, leaving them frozen and easily stricken down. For now it seemed that his marionettes were doing a marvelous job. The titan looked at his golden glove where the gems laid. "Rest my dears, rest. Why killing the fun? There is plenty of time for you to play along."