BINDING OF ISAAC and FASTER THAN LIGHT are NOT IN THE SAME GENRE

We tell you if a game is a roguelike or not.

A roguelike is a top-down grid-based RPG with procedural generation of at least some of the world and simultaneous turn-based movement. That's it.

Nope. It's common in roguelikes, but not mandatory. For example, permadeath is toggleable in ToME. The genre label "roguelike" does not describe that game any less accurately.

Nope. Rogue doesn't even have metaprogression.

Yes. But we have to live with it now.

Not the Berlin Interpretation. The Berlin Interpretation sucks. We follow the Yeoman definition, almost to a T. There can be minor variations to the basic roguelike criteria without the game ceasing to be a roguelike, such as being hex-based instead of grid-based in the case of Curious Expedition (which is indeed a roguelike despite being quite unusual within the genre). But the procedural generation, grid-based maps, and simultaneous turn-based movement are the most essential elements. If a game does not fulfill these criteria, it is not a roguelike no matter how much permadeath and metaprogression you slather on it.

Roguelites take the aesthetics of the roguelike but discard the essence of the roguelike, namely the unique movement and gameplay which no other type of game has. In practice, "roguelites" tend to be normal games with permadeath, meta-progression, and/or procedural generation. Notice how these things barely, if at all, describe the actual gameplay of the game. These are not core genre attributes, these are modifiers that can be applied to basically any game. Super Mario Bros with permadeath and metaprogression is still a 2D platformer. I am aware that I'm making a lot of assumptions with these statements, one of the biggest of which is "a game's genre should mostly, if not entirely, describe gameplay". I think this is a reasonable assumption and will not endeavor to make a defense of it here.

Nah. I'm just doing this for fun.

Nethack. It's very good.