It had been a long time since the assassination of the old queen and king. In that time, Undyne had trained herself to perfection. She would NOT let Asgore die. Currently, though, she couldn't do anything to protect him. She was deep in human territory, nearing a village with a weapons factory. Despite what the humans believed, she wasn't there with an army. Rather, she was there with fifty hand-picked troops, the best she could find. The only other monster there was Toriel, a young monster who was a strategic genius. They had been in the pine forest nearby the village for two days now, and were almost ready for the attack. Every monster in her force was equipped with a Magic Ability Extender, an arm-mounted device developed by the illustrious Dr W.D. Gaster that boosted magical power, allowing for longer-range, more powerful attacks. Unfortunately, Undyne couldn't use these gadgets, as whenever she tried, they exploded. But at least every other warrior was equipped with one.
Undyne looked out from the forest, towards the strange village. It was surrounded by a metal wall, topped with barbed wire. The humans should have known that it was a futile defense against magic. The real problem were the red-armored guards that patrolled around the settlement. Their numbers had been picking up recently, as if someone knew they were coming. But it didn't matter. Her force was too powerful to be stopped by a few human soldiers. She stood up. The sun was almost down. It was time. Undyne ran to the camp, into Toriel's tent, and told her to help get the troops ready.
Fifteen minutes later, the monsters marched, with Undyne and Toriel at the head. Undyne had never seen Toriel fight, but she was known to be a formidable opponent. The humans were ready for them, confirming Undyne's suspicions. Row upon row of red-armored soldiers were lined up in front of them. The outer columns were made up of masked soldiers in leather armor, wielding knives. The same knives that slit the old King's throat. In between those were columns of heavily armored soldiers with axes. On the wall were more leather armored soldiers, these with crossbow-like contraptions. Suddenly, the first blast was fired, an arc of energy slamming into the ground behind her. A Knight-Knight just barely dodged out of the way. Toriel summoned a fireball in her hand, and with a flick of her wrist, flung it into the offending soldier, who blocked it with his crossbow. The rest of the guards then charged, silently. The only sounds they made were those of their feet and armor as they rushed the monsters. The Knight-Knight who was almost hit slammed her morningstar into a soldier's head, knocking him over, then brought the bottom of it down upon his armor as hard as she could. Meanwhile, a barrage of fire rained upon the assassins, who dodged it with ease. Undyne, however, leaped right into the fight, not waiting for it to come to her. All of a sudden, she was right behind one of the axe-warriors, driving her spear through a chink in her armor. The soldier collapsed, and Undyne impaled another one, who was going for one of the Madjicks hemming in the humans, on a spear that rose from the ground instantly. She froze another, and barraged him with spears. He blocked a few, but succumbed to the rain of spears quickly. A helix of fire shot by her helmet, hitting a sniper on the wall in the chest. A magical sphere went hurtling past, summoning crosses to trap a group of soldiers. Undyne leaped over it, and plunged her spear into the ground. All around her, spears rose out of the earth, skewering every soldier nearby. She yanked her spear out of the ground, and looked out at the battlefield around her. There were no humans remaining, and almost no dust anywhere. In just a minute after it started, the battle was over.