It’s sad but true: your cows have been infected by a strange disease. They are getting mad. Your only chance is to pick out the infected animals and get rid of them. You have 60 seconds to find 30 mad cows. Note: A healthy cow is behaving exactly like a cow should do. So avoid these as it'll cost you 10 seconds off the clock for putting a healthy cow down. . Use your MOUSE

It’s sad but true: your cows have been infected by a strange disease. They are getting mad. Your only chance is to pick out the infected animals and get rid of them. You have 60 seconds to find 30 mad cows. Note: A healthy cow is behaving exactly like a cow should do. So avoid these as it'll cost you 10 seconds off the clock for putting a healthy cow down. . Unfortunately your cows have been infected by a strange disease....find them and put them down.
Use your MOUSE

In Quake II, the brutal Strogg attacked Earth, looking for fresh ways to re-supply their cyber-organic army. A lone marine broke through their defenses and defeated their leader, the Makron. The Strogg built a new Makron, however, and in Quake 4, you must join the invasion of the Strogg homeworld, where humanity’s only hope lies in your ability to access the highly-fortified structure containing the Nexus Core. There, you can disrupt all Strogg communications and give the marines the upper hand.