One of the best parts of the Minecraft phenomenon is the community and their creativity. It's so impressive in fact, that many of the user-made mods out there do far greater things than the stock Mojang version of the game can do. Some of the mods have even found their way into the actual Minecraft beta, including but not limited to, the lighting mod, the world selector and the upcoming Pistons mod (read all the Minecraft 1.5 update details for more).
If you're into expanding the Minecraft gameplay with user mods, whether that be through fun things like the Planes mod or the themed FPS mods, Minecraft Predator and Halocraft, then there's another shooter entirely you may want to look into: Ace of Spades.
Dubbed "Minecraft with rifles," Ace of Spades is a team deathmatch style game where two teams (blue and green) of up to 16 players can fight each other and complete objectives, Minecraft style. The goal of the game is to attack the opposing team's base, steal the intel (a briefcase) and bring it back to yours. The added twist of course, is that you can alter the environment and hence the comparison.
You'll be able to dig trenches, build tunnels, bridges and bases and these are affected by the mod's physics. If you shoot the support beams on a bridge, the whole thing will fall down.
It's got its own first person shooter control scheme, with number keys 1-5 corresponding to different weapons, "R" is reload and right-clicking lets players look down the weapon's sights, etc.
Headshots do more damage and grenades actually blow up blocks - that alone sells me on wanting to try it out. For more information on Ace of Spades details, click here to see the full game guide and for download/server info, head to ace-spades.com.
The only downfall with the current version (0.26) is that there are no textures and it looks like the Alpha build of Minecraft. That'll no doubt change if they get donations and Ace of Spades grows in popularity.
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