A challenge where you put a bunch of mentos in your mouth and trying to consume a 2 liter bottle of diet coke spilling as little as possible. The chemical reaction produced by the coke interacting with the mentos causes it to burst out causing people to spill coke while consuming it.
The act of inserting a full package of mentos to the inside of an asshole during anal sex and - subsequently - adding your jizz and a glass of diet coke to the mix.
Drinking the ensuing mudslide is optional.
Jerry gave Melanie the best mentos mudslide ever; she gaped like a pro and the ass-geyser was at least 7in high!