i shit trains
To shit trains typically means you are the shit. It can also correlate to being number one at everything. Often times used for upping a Mister One Upper, or someone who has to beat you at every event, activity, or story you've ever encountered.
John: I went to France.
Tim: I went to France 3 times.
John: I SHIT TRAINS NIGGA! NOW WHAT?!
Tim: I went to France 3 times.
John: I SHIT TRAINS NIGGA! NOW WHAT?!
I Shit Trains!
The act of shitting out a train by the power of Unknown forces.
The cops was about to get my ass so I yelled, "I Shit Trains!" And by the power of the Unknown I shat a train that derailed another train and killed dem.