>>43351055I stand in front of the train and ready an attack of opportunity. I will take a lot of damage from the hit, but as a Senior Paladin I am presumably high enough level that eating 100 hp worth of damage is something that I can survive, especially if I have any time to cast a defensive buff or two. Between that and the attack of opportunity, I am reasonably sure that I can stop the train in its tracks, saving everyone but myself.
Worst case scenario I stop the train at the expense of my own life. Which, as a Paladin, is my duty should the need arise.
Afterwards I Lay on Hands myself back to a reasonable amount of health, make sure that everyone on the tracks or the runaway train gets whatever healing they need to pull through this, and then question the unfortunates on the train tracks.
Having saved and freed these good people, I set out to track down the twisted jerk who is tying people to railroad tracks for kicks.