April Fools' Day is a grand tradition in the world of video games, the one day of the year when publishers, developers, retailers, and gamers alike delight in the opportunity to share a laugh. It's a day full of fake announcements, self-reflective stunts, and, most importantly, funny videos.

　　Without further ado, here is a roundup of some of the best shenanigans the gaming industry has had to offer on this very fine April Fools' Day 2012.

　　Valve's Half-Life 3 stunt

　　People who visited Steam's website on April Fools' Day saw this. It's Valve, being very, very cruel. And just so you're completely certain that yes, it is actually a joke and Valve hasn't made one of the biggest and most long-awaited announcements on the day dedicated to pranks, clicking on the announcement brings up this little gem.

　　Minecraft creator announces "Mars Effect"

　　Minecraft creator Markus "Notch" Persson took the mickey out of everyone today with the launch of this website. According to the site, Mojang's latest title "is still very early in development" but will feature delightful things such as "hard science fiction," "lots of engineering," "space battles against the AI or other players," and, this is the best part, "a game ending that makes sense."

　　Assassin's Creed for Kinect…now with hay bale hiding!

　　Just to be clear: it wasn't Ubisoft that made this, but rather a very savvy YouTube user who created a trailer for what Assassin's Creed might look like if it were to fully take advantage of Microsoft's Kinect motion-sensing system. Note the very impressive "hiding in a hay bale" position, and our personal favourite: running around in circles.

　　Rock Band: The Board Game

　　Harmonix decided April 1 would be a good day to announce its new project: a board game edition of the popular Rock Band franchise. It might just be crazy enough to work. Go on, download the board and play at home, we dare you.

　　"We know you've been on the edge of your yoga ball/standing desk to see what mind-blowing game Harmonix is going to make next. Well friends, that wait is OVER! Feast your eyes and ears on this EXCLUSIVE commercial for our upcoming game!"