The add-on begins Saturday morning, with the Dude waking up in the hospital, his head bandaged from a near-fatal gunshot wound (while the Postal 2 ending leaves it ambiguous as to whether or not the Dude shot his wife or if his wife shot him; after he wakes up in the hospital he finds a card from his wife saying that she is leaving him. (It was recently revealed on the official website that the Dude shot himself due to his wife nagging him). The Dude proceeds through several missions including assigmments from his former employers (RWS), encounters with zombies, and encounters with terrorists and the military. Periodically Dude's head wound causes him to enter a nether realm where he is attacked by creatures resembling Gary Coleman. Dude's ultimate goal is to recover his trailer and his dog.
The expansion adds several new weapons, including a machete which can be thrown like a boomarang, serving as both a close- and long-range weapon, as well as sledgehammers and scythes which can also be thrown. Unlike the main game, Apocalypse Weekend also includes several "boss monster" encounters
A bug noted in the version available for Mac and Linux results in the Dude character being headless throughout the game (this is visible during cutscenes and when looking into mirrors).
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