This game is so interesting because most of the mechanics are like the ones in real life, exept for the saving and loading mechanics, ofcourse. What I mean is that like this reality, the UNDERTALE universe is SOULly (Alexa, please laugh)based on your actions. People will know if you murder someone, people will acknowledge if you don't murder, people acknowledge when you save and load, hell theres even a boss fight based around the premis of saving and loading the game's files! It's an emotional rollercoster aswell, once you take a true pacifist route, it'll be near impossible to hurt any of the NPCs. All the characters have their own morals and uniqe designs, I'll let ya figure that out on your own. But in the end, Undyne is best girl, I cried alot and it takes alot to get me to cry so that's something to take into account, and Asgore's theme is underrated, g'day.