10 Worst Video Game Choices You Regretted The Entire Playthrough
2. Killing Tutorial Characters - Undertale
By now, pretty much everyone is aware of Undertale's twist ending.
If you follow your RPG instincts and kill monsters for EXP (Execution Points), you get the genocide ending, but if you never lift a finger on the underground's residents, you get the pacifist ending where everyone lives happily ever after.
Well, this plot twist wasn't so obvious when most people started playing the game, and the mistake most players made in the tutorial would haunt them for the rest of the playthrough.
At the start of the game, when the game explains the combat, it doesn't really elaborate too much on how the spare mechanics work, which is why it's easy to end up killing one of the tutorial frogs.
On top of that, it's also easy to kill Toriel, since the boss fight with her deliberately doesn't make it obvious she is spareable.
Killing even one monster is an honest mistake, but it will still immediately prevent you from doing a pacifist run. You'll be stuck on the neutral path at best, and you'll have to play the entire game guilt-ridden before you're given the option to go back in time and fix your mistake.