Poopdeck is made of two words, poopd and eck. I believe they are German. It involves a fetish game where several drunken German folk get on a patio with all the rails removed. Ten they get a fecal freakal and the deck gets all slippery with poo, right? Then one guy (any one, nobody is picked) jumps up and yells SHIVAR ME TIMBEEERS (But in GERMAN dude!) and they all try to push their slippery, excrement-laden partymates off the deck. It's like King of the Hill, except (a) everyone is covered in shit, (b) it's technically a plateau, and outside the Bavarian Max players (deck height 3 meters) most decks are made close to the ground to avoid injuries. At the end, the last person standing wins. If the Shiver caller is the winner everyone buys him a beer. If someone ELSE is up there, the winner can pick to have the caller buy him a beer, or everyone gets to pee in his eyeballs.
Trundel and Hans are having a poopdeck party, bring the keg, exlax, three shower curtains, and laundry detergent!