Multi Use / Genre RPG Systems

[The NPC]

I am looking into multi use rpg systems. Such as Savage Worlds or Cypher System.

I have experience with the above two. What others would you fine individuals recommend?

[Bluenose]

There are a lot. At the high end of the complexity scale you've got GURPS (highly simulationist) and HERO system (very toolkit). Intermediate complexity would include Fate (quite narrative) and Chaosium's BRP (more simulationist). At the low complexity end Fate Accelerated and Heroquest (2nd edition, or Heroquest Glorantha, are the best versions). There are also games using the same/similar systems for different titles, such as the PDQ system, the various ones derived from BRP (including Call of Cthulhu and Runequest), or several D20 System games.
Which I'd recommend depends on what exactly you want to do, as they've got different strengths and weaknesses. Gurps and BRP wouldn't be my choice for a superheroes game, but Hero and Fate manage that well. Fate Accelerated and Heroquest wouldn't be good choices if you want to know How you arrive at the result of an action - they're both quite abstract. Heroquest gets an astonishing level of character customisation by making abilities very abstract and task resolution lacking in detail. It's hard to recommend any particular one for all situations.

[The NPC]

Going for a real world setting where the players a people who died, went to Hell, and came back when the barrier got weak and upon arrival back it turns out they have become demonic in nature with powers reflecting their torment in Hell.

[Bluenose]

The NPC wrote:

Going for a real world setting where the players a people who died, went to Hell, and came back when the barrier got weak and upon arrival back it turns out they have become demonic in nature with powers reflecting their torment in Hell.

Not really something I see Fate, FAE or BRP doing well. I'd expect GURPS to have some way to handle it, but not necessarily in the core rules. That would leave HERO System - Champions, specifically - or Heroquest. The first is very good for putting together self-designed suites of powers under point-buy. The second would work with a keyword tied to the power(s) that the character had, and allowing them to advance it before play to a fairly high level.

[The NPC]

Interesting. Something to take a look at in the coming weeks.

[GM SuperTumbler]

Depending on the power level you are going for, Mutants and Masterminds would probably work.