Undertale + Spec Op The Line spoilers
One thing that I still really appreciate about UT was the story's explicit understanding and integration of player control. Something SO:TL and UT share is that they both make commentary on your actions as a player, and how you are complicit in the violence depicted. However, SO:TL takes a sort of... easy road. You have no other choice except not play the game. And given that it costs real world money? That's just a copout, I'm sorry.
Undertale + Spec Op The Line spoilers
In SO:TL, you have no option but to do terrible things. Your options are either do it, or fail to progress. How can your decisions be bad if you aren't making them? It ultimately turns you into a spectator while commenting on you as if you were an actor.
Meanwhile, UT acknowledges you have power. It says "I know you can reset. You can try as many times as you like to do this." and every interaction in the story is cognizant of this.
Undertale + Spec Op The Line spoilers
Did you kill Toriel? Well, maybe you haven't noticed yet, it's been pretty easy so far... Did you kill Papyrus? Maybe... you weren't paying attention. But the deeper in, the more it questions you, grills you, and tries to point towards your power. Sans, at the end, finally calls you out, explicitly pointing to how much power you have. Are you sure you WANT this? Do you CHOOSE this?
Undertale + Spec Op The Line spoilers
In UT... there are multiple creatures trying to kill you. Why? Why do you need to be pacifistic towards them?
This all comes back to the nature of DETERMINATION and the power of humans in this world. Every time they kill you, you just... aren't dead. You go back. You keep retrying. Literally, as long as you are determined to stay alive, you can not be killed. You are in ZERO danger. They try so hard because anything less dooms them to failure from the start.