Zombies have already taken once to the streets of Bristol and will return tonight and tomorrow as part of 2.8 Hours Later, the headline game of this year’s igfest, the Incredible Games Festival, returning to Bristol this weekend for its fourth year.

igfest is a chance for imaginations to run wild and the streets to become your playground. Decide whether you are the cowgirl or the cow in Cowgirl Rodeo. Who will win in Angry Balls? Or play Arcade Anarchy, the giant Tetris game – run the course, dodge the baddies and beat down Pacman, Mario and the Space Invaders.

Nothing should be a surprise. Seek ‘n Spell is a citywide game of Scrabble using GPS phones. Gigaputt also used GPS to play a citywide game of golf, using your handset like a Wii remote.

Meanwhile, postboxes are interplanetary; circle rules is a mash-up of football, volleyball and basketball played with a yoga ball; and Gate Crash is the hunt for Bristol’s greatest party following a series of clues.

igfest 2011 brings together the world’s leading games designers for the very first time, with games from New York’s Come Out and Play and San Francisco’s SF0, London’s Hide & Seek and Bristol’s own SlingShot.

Visit igfest.org for the full programme of activities, and watch out for those zombies.