Undertale is an Indie game made by Toby Fox. this game was not very well coded but it was very well written. Most games do not treat the player and the character as seperate entites. This game does and also Toby Fox’s second game Deltarune where it is more obvious. Anyway, Undertale also treats the Save and load system in video games as and in universe thing and not and video game thing. So for context Humans and monster (Creatures made of magic). Lived together for many years untill a war broke out and they humans won sealing the monsters underground with a spell that can only be broken by 7 Human souls. But monsters can leave individually by absorbing 1. After the king of the monster’s son died. He waged war on humans again in a fit of rage and started to collect souls of anyone who enetered the underground. Also flowey a being with no soul was created using the remains of The king’s son. flowey knows about the SAVE and LOAD system and abuses it to kill people over and over again. Untill, the human you control Frisk enters and Gains priorty over the SAVE and LOAD system through Determination. So from this point on there is 3 routes you can take the True Pacifist where you spare every monster and free them but this requires a netrual run to be done before which is just a mix of sparing and fighting and then the genocide route Where you kill every monster in each area, it is the most boring but the hardest becuas eof 2 fights. But Characters will call you out and call you a terrible person for killing everyone for no reason. So I think it’s writing shines in using video game tropes to it’s adavangtage in thw writing.