F-side Games

Beyond the veil of reality, beyond the influence of manipulating politicians, greedy merchants, iron-handed clergy, and the broken masses that toil for their benefit, echoes of other realms call to those bold enough, and desperate enough, to escape the oppression of mundane life. Treasure and glory await those courageous enough to wrest it from the darkness. But the danger is great, for lurking in the forgotten shadows are forces far stranger and more perilous than even civilization. The price of freedom might be paid in souls.

Lamentations of the Flame Princess (LotFP) is an old school weird fantasy role playing game with firearms rules for an early modern setting. 

Because of the illustrations and some of the themes covered, this game has an 18+ recommendation.