u/Sea_Basil_361

You were tied to the track by morally ambiguous time travelers and they tell you some horrifying things. A trolley is heading down the tracks and will go through a rip in time, killing future you, which will directly cause the apocalypse. If the apocalypse happens, everyone you love and care about is guaranteed to die painful deaths. You are close enough to the lever to pull it, in which case you will die a painful death, but future you will not exist and the apocalypse will not happen. Other than tying you to the tracks, the morally ambiguous time travelers can do nothing and must return home before you make the decision.