Chapter Text
Heimdall could not see everything, he was not powerful enough, but he did have the power to see anything. At least that is what he had believed until he heard a noise coming from his left. Standing on the Bifrost he looked out across the waters on the periphery of Asgard and did not see anything; but he did see the effects the thing was having on the world. A ripple in the air and the resulting minuscule bending of the light were all that betrayed the approach of the spacecraft to the city that Heimdall was sworn to protect. Lacking any better options and the time to come up with something he threw a knife at the disturbance and was rewarded with the sound of breaking metal. The stealth field hiding the craft failed shortly after, revealing what looked like a flying dagger. It was a drone of some sort, packed with electronics leaving no room for any kind of crew. Heimdal spotted a small but important looking vent and thew a blade directly into it. This time he was rewarded with an explosion that split the craft into two pieces that fell into the water.
And then dozens of identical crafts simmered into existence as they abandoned their stealth approach and accelerated toward the palace at the center of the city. Heimdall did not know who was attacking or why, but that the city was under attack was clear enough. His duty now was to sound the alert. He ran back into the Bifrost and placed his sword into the control sheath and activated the alarm.
Immediately the city sprang into action, anti air towers sprang to life and began attempting to shoot down the attacking drones; but they had been designed for attacking an enemy at longer range and had trouble tracking targets that had already reached the city. The drones do not fire back as one might expect, instead they acted more like the flying knives they resembled and closed the distance to the towers in order to collide with them and sever the barrel of the guns. The exchange left the defenders reeling as they lost almost all of their heavy anti air guns. The last of the drones were shot down by Asgardian air ships that had finally managed to scramble. But there was nothing in place to defend against the troop transports that had followed in still invisible behind the drones.
Only one of the transports was shot down, the rest landed and disgorged enemy troops into open spaces, stadiums and parks mostly. It was now that the defenders saw who they were fighting, Dark Elves. The Elves set up portable shield generators to protect from air attack and began digging in. An apparent mistake on their part to surrender the momentum of the fight. Troops poured out of the Palace and assembled at preplanned locations and prepared to counterattack the invaders. Heimdall ordered the shield raised around the palace as soon as the Asgard garrison had left. It was at this point that Heimdall saw just how much he had erred. Somehow there were already Dark Elves inside the Palace, a group was even inside the shield generator room. They attached a device of some kind to the generator; it siphoned a small amount of energy and diverted it to the walls effectively sealing the room. When Heimdall tried to turn the shield off he found he could not, he had been locked out of the system.
Heimdall could see, looking carefully for signs of any further invisibility trickery, that there were approximately the same number of soldiers on both sides. But one third of the Asgard soldiers were guarding the weapons vault, they would not leave that post to save even Odin. The Dark Elves in the city turned around and walked back into the transport ships and left under the cover of cloak, what happened next would be decided by the people who were already inside the Palace.