Usually Valve unleashes multiple Steam Early Access games each week. For this week though only one game made it through. Perhaps this means Valve are being more cautious with the games allowed on the service? Or maybe they're just taking a little break before hammering users with a million more alpha/beta games next month.
In any case, a really promising title just hit Early Access and it's Mercenary Kings. Although the game is still in beta, Tribute Games have already provided a fairly solid product. The current version available already includes 60 missions! According to the developer, they're aiming for over 100 missions in the final release.
The 2D shooter looks like a mix of Contra and Metal Slug with really appealing pixel art. Both single and multiplayer co-op are included (local or online). If you're interested in Mercenary Kings then be prepared to spend $14.99. Or, if you are willing to bet that you (and three friends) will love the game then try out the 4-pack for $44.99.