The latest Humble Monthly Bundle has three excellent early unlocks if you stump up $12: narrative card game Cultist Simulator (one of our favourite games of last year), co-op monster slayer Warhammer: Vermintide 2 (one of the 100 best games on PC) and giant ant killing sim Earth Defense Force 4.1, described by Phil in his review as "very videogames".
Pay $12 now and you'll be able to play them all straight away, plus you'll get a handful of mystery games in March. Technically, you're subscribing to the bundle on a rolling basis when you sign up, but you can cancel (or pause) after one month.
I'm tempted to buy it for Cultist Simulator alone—according to deal site IsThereAnyDeal, the lowest it's been on sale for is $14. As Chris wrote in his review, it's a deep and challenging card game with excellent writing, and half the fun of it is figuring out how it all works.
Vermintide 2 is another that you should add to your library if you haven't yet, especially if you have friends who can play it with you. You can check out Stephen's review here: it's basically Left 4 Dead meets apocalyptic fantasy Warhammer, but with loot.
Think of Earth Defense Force 4.1 as the extra stocking stuffer. "No polish or refinement, just lots of giant ants and plenty of ways to kill them. Ridiculously fun at its best, which it frequently is," said Phil in his review.