If 2D Metroidvania is more your taste, then Axiom Verge is just the game for you this Halloween season. Drawing inspiration from Super Metroid, among other titles, Axiom Verge places you in an unknown environment that blurs the lines between reality and the subconscious. You end up there as a result of a lab accident, so you're not entirely sure at first if you're alive or not.
However, the game gives you a great deal of control over your environment through the glitch mechanic, letting you manipulate your weapons, enemies, and even landscapes -- some you might not have been intended to see. There's a deep story here, too, as you'll uncover the remnants of an ancient, apocalyptic war and try to piece together how this domain ended up the way it did. The entire affair is rather dark and moody, as you would expect, and it's an excellent way to add some atmosphere to your Halloween gaming.