run a train

verb3

1. •
   (slang, vulgar) To have sex with someone multiple times in short succession.
2. •
   (slang, vulgar) Synonym of gangbang: To have sex with someone as a line going one after the other.

   • And we went upstairs and we ran a train on her. — 2008
3. •
   (slang) In online games, to lure large numbers of NPC enemies to a fortified enemy position in order to cause chaos and destruction