The fine art of gobbling as many XTC pills as possible in a single night. Preferably in a dark, maze-like room with other people wearing multicoloured sheets on their heads.
"Let's head out to the club and munch pills like in the arcade. It'll be fucking pacmania!"
A trip to a grocery store, convenience store, or gas station for the sole purpose of buying an excessive amount of junk food and sugary drinks, usually with friends. A chud run often happens late at night and ends with everyone involved hating themselves afterwards.