After playing all HALO games I have come to the conclusion that there is only 3 kind of enemies. First are the ones who follow the rules. These are basically the Covenant. For Religious belief or for honor to the cause. The covenant will NOT stop until they accomplish there goal. Also this is the biggest/larger group. The Second group are the wild beast aka zombies (the flood), these don't really know the difference between right and wrong, they just want to feed themselves like hungry beast. There motive is haunt and eat. In Halo CE were like that. The third group are the machines, these enemies can fight against you or with you. There is NO moral, belief or purpose behind. They just follow the codes that they are design to do. This kind were very noticeable in HALO CE and HALO 2, when guilty spark 343 send his Sentinel to help you with the flood, and then after the job was done he send the sentinels to attack you. There was another kind foe in HALO games but very brief, the civil war Covenant Elite in HALO 2. This guy din't want anything with the covenant , his motives were different . He was anarchist , a rebel. crazy thought... If he had team up with MC, he might had a chance to survive. what you guys think ?