Pain Train (Fallout 4)

Pain Train is a perk in Fallout 4.

Effects
The perk grants increased damage and chance to Stagger enemies if run into while wearing Power Armor. Hitting enemies with Pain Train rank 1 or 2 will give them a buff that makes them immune to Pain Train for 6 seconds, hitting them with rank 3 will extend that buff to 12 seconds. Each knockdown uses 10 AP and each knock back uses 20 AP.

Behind the scenes
Pain Train works very similar to Shield Charge from The Elder Scrolls V: Skyrim. Due to both games utilizing the creation engine, it acts and performs the same in the way that enemies bounce off the player character as they strike them.

Bugs
This perk can stop working without reason, preventing enemies from being damaged, staggered or knocked down, as though the Perk was never taken.
 * This bug can be fixed by entering the following into the console: