Intro: Why replaying Undertale is a delightfully chaotic idea
Undertale is one of those games that treats your choices like precious, fragile candy — every decision nudges the story down a wildly different path. There are four main routes to chase: Neutral, Pacifist, True Pacifist, and Genocide. Each one has its own scenes, boss fights, and endings, so if you’re the kind of person who likes collecting digital chaos, you’ll want to try them all.
Routes at a glance
Quick snapshot so you don’t get lost: Neutral is the default, Pacifist means spare everyone, True Pacifist is the full warm-hug ending, and Genocide requires wiping out every enemy. Yes, really every enemy.
Neutral Route
This is the route most people stumble into on their first playthrough because it doesn’t demand strict behavior — kill or spare as you please and the story will still push forward. It’s the chill, ‘I’m seeing how this goes’ run.
Pro tip: If you want to see multiple endings without replaying the entire game from scratch, try finishing a Neutral run without killing anyone and save before the final boss. That way you can reload and pursue another route without retracing every step.
Pacifist Route
Pacifist is all about mercy. To pull it off you must avoid killing any creatures or bosses and be mindful of a few key side events that unlock the true warm-fuzzies later. It’s trickier than it sounds — mistakes are easy to make if you’re trigger-happy.
Helpful steps (in plain English):
1) After your encounter with Papyrus, visit his house again to trigger and finish his side-quest—this keeps his storyline moving the right way.
2) The Undyne encounter is special: during part of the fight your heart’s color and mechanics change, making fleeing tricky. When you get a chance, run away and progress until you reach the bridge in Hotland. There’s a scene where you can use cold water to incapacitate Undyne briefly; later you’ll return to finish that arc in Waterfall.
3) Around the bridge between The Core and the MTT Resort you’ll get a call that sets off a chain of events: a letter ends up at Papyrus’s house and taking it to Alphys kicks off her personal questline.
4) Complete Alphys’s quest and remember to check the bathroom in her lab — that’s the secret doorway into the Royal Lab, which you need to access for the full Pacifist progression.
True Pacifist Route
True Pacifist is the deluxe, extra-sappy ending. To unlock it you must complete the Pacifist requirements and also finish the additional friendship-focused events (Alphys’s side stuff and the hidden lab sequence). Do all the kind things, tick the boxes, and you’ll get the full heartfelt finale.
Genocide Route
Genocide is the opposite of Pacifist — it’s grim, intense, and unforgiving. To follow this path you must intentionally defeat every encounter in each area until no monsters remain. This route changes the game world dramatically and isn’t reversible on the same save without some fuss.
Area enemy counts you’ll need to clear (so you don’t accidentally skip one): Ruins: 21, Snowdin: 17, Waterfall: 18, Hotland/Core: 40, New Home: 1. If any area’s quota isn’t met, the route won’t proceed properly.
Final thoughts
If you want to experience everything, play smart with saves: finish one route, keep a backup, then try another. Treat your save files like fragile artifacts, because Undertale will absolutely surprise you. Most importantly — enjoy the absurdity, the feels, and the soundtrack. Go wild (responsibly) and have fun exploring every weird corner of the Underground.
