The Flood

Flood Spore Flood Spores are tiny creatures that look a bit like a jellyfish. They attack by attaching themselves to their target. If they succeed, they target becomes infected and turns into a Warrior. They do very, very little damage, but sometimes travel in packs numbering in the dozens. When they are killed, they explode, damaging nearby creatures.

When encountered in groups of a dozen or less, fighting Spores is blindingly easy. All you have to do is stand there. They attack, and, upon hitting your shields, die. Your shields can easily absorb 20 or so Spores before they run out. If you encounter a few Spores, just take the hits and wait a few seconds for your shields to recharge.

When encountered in larger groups, the technique for disposing of Spores isn't much more complex. They are slow-moving, so just play keep away for a few seconds until they start to bunch up. When they do, kill one. It will explode, killing the ones next to it, which explode in turn, killing the next bunch, and so on. The chain reaction can sometimes result in several dozen kills from a single pistol shot.

When encountered in groups, the best strategy is just to fire a quick burst from whatever weapon you have at the moment, killing most of the Spores, and then simply absorbing the hits from the others with your shields.
No weapon is more or less effective against Spores, as any hit from any weapon will kill them every time. Grenades tend to be overkill, as do rockets, but anything else works just fine.
Flood Warrior Flood Warriors are Human or Covenant troops who have lost a fight to Spores and have become infected. They bear only a vague resemblance to their former selves, but can use any weapon found in the hands of a Human of Covenant soldier throughout the course of the game. They do not use vehicles (or stationary guns). Occasionally a wounded Warrior will 'play dead,' dropping to the ground and staying immobile until a likely target strays near.


Warriors attack with weapons most of the time. If they have no weapon, they attack with an unarmed strike that can be severely damaging. They also have the ability to make astounding leaps, and can attack while in the air. They will often use this leap to reach otherwise inaccessible places or to close quickly with an enemy when unarmed.

The two best weapons to use against Warriors are the shotgun and the pistol. A shotgun blast from close range will kill any Warrior in one shot. Pistols do serious damage to Warriors, and two or three shots to the body will drop them. Additionally, pistol shots will sever a Warrior's limbs, and a shot to the head is almost always instantly fatal. The sniper rifle is equally effective, but Warriors tend to travel in packs, and sniper ammo is rare. Plasma weapons are particularly ineffective against Flood troops, and this includes plasma grenades. Frag grenades are as effective against Warriors as they are against anything else.
Flood Carrier Flood Carriers are bloated, walking Spore nurseries. They don't use weapons and have no regular attack, but if they get close to an opponent, they will explode violently enough to drain your shields almost completely. Furthermore, once they explode they release a half-dozen Spores. Carriers are at their most dangerous when they surround you, as they can close in on you from behind while you are busy killing the ones in front.

Carriers are easy to fight, at least as long as you know that they are there. A few shots from a pistol or assault rifle, or a single shot from a sniper rifle or shotgun will kill them easily, causing them to explode and release their Spores. Other weapons are less effective against them, but they move very, very slowly, giving you plenty of time to shoot.
Wise players won't shoot Carriers on sight. They are not a threat unless they are close, and they often travel in the company of Spores and Warriors. Watch the Carriers and wait until they are close to another enemy or two before shooting them. The resulting explosion will damage or kill all of the nearby creatures. Be careful; exploding carriers will also cause any grenades lying on the ground (such as those dropped by killed creatures) to explode on the spot, compounding the damage.