Technically just one but I call them different names to seem like I'm versatile. The Ganja car, the weed car, the bud car, the Mary Jane car, the pot car and the Reefer car. Cheers!
My train-of-thought is pretty much standard in number of cars. The only thing about them that differs from the norm is all the glitter-graffiti they're adorned with. And don't even get me started on all the derailments and side-tracks my cognitive choo-choo takes.