Ever wondered what it was like to be an antibody? No, we don't suppose anyone has but if you've ever felt like trying to visualise the fight your little microscopic guys were up against to keep the threat of infection at bay, then we reckon it probably looks something like this.

Antigen

Format

Android

Price

Free

Where

Android Market

Antigen is a where Arkanoid meets Tetris inside someone's body cavity. You are a little square-shaped antibody with four different surfaces which house four different lock and key mechanisms for vanquishing any nasty antigens that pop up in the blood stream. Each baddie requires a different side and your job as the player is to rotate your little antibody so that it's facing the correct way, before you steer it into the path of the antigen which it can then lock onto and destroy. Got it?

Naturally, you have a steady stream of enemies that begin to come thicker and faster as you reach heavy infection zones and at the end of each of the five levels, you'll even have a boss virus to contend with while still trying to stop its minions getting to the other side. And, if you think that sounds too tough for you, fear not, there are power ups to help you out on the way.

You can choose from all sorts of levels of difficulty and from story or survival mode but it's the free price tag on this one that makes it well worth a download. It's very playable, there's a nice level of humour and it'll keep you interested for a couple of weeks before you decide not to upgrade to the paid version.

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