Aqua Regia is about a mercenary in a dictatorial country, a fairly typical Cyberpunk setting, set in South America (Specifically Argentina, but only at the beginning), which has been on a dictatorship since 1976 (and counting). The year is 2056, Daniel, a mercenary, who in a twist of fate, interrupts a robbery in a local market, fighting with a thief, and ends with him joining a group of resistance led by a woman called Nimsi.

From that point onwards they'll be battling off against criminals, terrorists, and even a corrupt government, while recruiting people for the cause, all over the globe. Nevertheless, nothing is as easy as it seems, from the rift of time humanoids called Moaerus emerge and have a vendetta against his group, for some unidentified reason at the beginning, but later is revealed that the world was rebooted, so to speak. And the souls of those who defeated them in the previous cycle have reincarnated, and the only survivor of the massacre, wants to take revenge on them, first reviving the leader of the Moaerus, and later remaking the world like it used to be in reality, full of nightmarish creatures (The designs of the monsters will be inspired in those of Hieronymus Bosch, Salvatore Rosa, and Zdizlaw Beksinski.

The ending will be either with the world becoming a post-apocalyptic fantasy world, a nightmarish landscape with advanced technology but terrifying creatures, or a more upbeat ending with the heroes winning, but the world pretty much screwed either way.