Combat Form

Summary
After an Infection Form has obtained a frequency match for the host's neural system, it begins to rewrite the very DNA of the body it's using. Once fully transformed, the Flood infection is in total contol of the body. Unfortunately for the host, he or she stays alive for the duration of the transformation process and is even conscious of his environment as the Flood takes over the body. Once completely infected, the Flood becomes a combat form. Any body capable of carrying a weapon or that is still useful in combat becomes a combat form and is very deadly. The Combat form grows whip-like tendrils on its arms, and will use them as melee weapons in close range, or if it loses its weapon.

The Flood infection is capable of not only controlling the host's body, but of also tapping into its memories to find relevant information about using weapons and equipment. In Halo 2, the Flood have learnt how to tap on the host's knowledge to drive vehicles. Some Combat Forms are equipped with energy shields or Active Camouflage. Combat forms are capable of using most weapons made by both humans and the Covenant.

After enough damage has been taken and the combat form cannot function effectively, it becomes a Carrier Form that incubates more infection forms. Eventually a combat form will mutate into a carrier, regardless of damage, to prepetuate the Flood species. Also in Halo 2, if not cut into pieces by an Energy Sword or other bladed weapon, Combat Forms can be "revived" by Infection Forms.

Note: ''The Combat forms can take extensive damage before being neutralized. Arms, legs, even heads can be totally blown off their bodies before they are incapacitated. The only known weakness of a combat form is its sensory feelers that normally develope in the upper chest region. This is where the infection form has nestled, and once destroyed, the body is incapacitated.''

The purpose of the combat forms is unclear. They are likely agressive by nature to all creates they come in contact with so that the creature's body may be assimilated into a Flood and used to prepetuate the species. They also probably assist Infection Forms in gathering bodies and performing actions that require a more sophisticated form.