Dungeoneering in space! With gritty not-space-marines! Fighting improbable and often silly monsters in order to scavenge food and fuel for their communities back home. This got ridiculously huge and grandiose, eventually incorporating giant transforming mechs and a battle to escape the solar system before the combined forces of entropy and fascism strangled life as we know it.
Absolutely bonkers game. Print-and-play. For three to six players, one of which is a GM.