Heroes in Time is a generic system that nevertheless comes with a huge range of settings, all tied together by a time traveling/ alternate histories theme.
The conceit of the game is that characters will be recruited from across the timeline of the game world. They will range from primeval barbarians, through fantasy elves, swashbuckling pirates, steampunk adventurers, modern investigators, super spies, and cyberpunk operatives, to the psionic knights of space opera.
All these different types of warriors will be recruited by an enigmatic group of Temporal Guardians and all working together on the same team, ready to be deployed to any point in history.
So get Heroes in Time and start adventuring through the whole of history
From the introduction:
The idea of this game is to provide everything needed to play any genre in one place – with the same setting so characters can travel backwards and forwards through time.
This RPG is the core system for the ‘Heroes in Time’ or ‘HiT’ role-playing game. The system uses percentile dice for most rolls, but it also uses six-sided dice here and there too.