An idea for an Alternative Genocide Route called "Special Genocide Route" and it's Final Fight and End. The Special Genocide would be only Possible to achieve after Making One Genocide Run (just like True Pacifist is only avalible after Getting one ending) and would be kind of a Subistitute of the "Souless Genocide" (q-q No,I don't hate Souless Genocide).The main characters start to notice the Character's behavior and start to Join together to evacuate everyone.But the Protagonist finded a Way to destroy the True Lab entrance door by using the Real Knife,and founded the Survivors.Then,returning to the New Home and reaching the Barrier Area,all the Seven plot-relevant Characters will await for you.After they talk about how they are furious at you,how you are Inhuman and how they will take revenge for the Monster race and save the Human race,they all use the Shared Power of the Human Souls as a Last Resort to Defeat you. So,the Last fight in "Special Genocide" would be basically You fighting everybody you mainly Helped in True Pacifist powered up by the Human Souls.They use the Same attack's they haved before,but in More difficult patterns and combined together.Attempting to attack them will result in Not giving damage because the Souls are too willing to help them save Everyone in the World that they literally maked them Invencible.The only way to progress the fight is to Hit the Souls (all them take 4-8 hits to defeat),making them Literally shatter.After shattering all the Souls,they lose all the Power,becoming what they we're before.After this,you lose input on the Fight as the Flavor Text reads "*I'll finish the Job." and Fight is automatically pressed,creating a Big side slash that hit them all in One shot and,after they last words,the Big side slash hit again,turning them into Dust.After that,The protagonist is in the Human Side of the Barrier,but before they enter the Door,they flip to the Screen,with Chara's face,Laugh and just after that they Enter.The game close itself like if it haved an Error and then,curiously,all the next Gameplay's of True Pacifist and Genocide won't be tainted by Chara's appearence unless if you go Genocide again. xP I know,Crazy but My mind do ideas like this... OBS: An theme for this fight lwould be something like this: https://www.youtube.com/watch?v=ArpPwj9B2Ms
Undertale belongs to Toby Fox