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Force 9 is science fiction role playing game inspired by Alien and Starship Troopers.
OPUS is a one page, universal role playing system.
In Darkest Warrens is billed as a minimalist RPG. Trollish Delver Games writes:
IN DARKEST WARRENS is a minimalist fantasy roleplaying game whose rules cover two pages, including a bestiary and introductory adventure. All you need is some six-sided dice, paper, pencils and, of course, a bunch of buddies to play with.
So what do you get?
All the rules you need, including character advancement for campaign play
Five classes: warrior, rogue, barbarian, mage and ranger
A bestiary containing 23 fiendish monsters to throw at your players
Super easy resolution system – all you need is a single d6
A character sheet
An introductory adventure: The Cow of Boburn
Hours of enjoyment in a small package
Print the rules right out and use them for reference at the table. Perfect for a pick-up and play game.
The game is available as a “pay what you want” from Drive Through RPG.