Combat Forms
-Combat Spider: An infected giant spider from the depths of a hive city. Range in size from 2-4 meters in height, while crouched. Eight legs and eyes, enhanced Flood senses. Able to emit Flood Spores from its lungs. Razor sharp mandibles and claws. Can crawl on walls and ceiling. Able to spit strands of webbing from its mouth. Webbing is very strong, able to trap beings of human strength. The webbing can be mixed with Flood Spores. Possesses a pair of whip-like Flood tentacles emerging from behind its neck which have superhuman levels of strength.
-Combat Centipede: An infected giant centipede from the depths of a hive city. Range in size from 3-4 meters in length. Powerful mandibles and tough hides, resistant to low caliber stubber rounds. Very fast and can crawl on walls and ceiling.
-Combat Wasp: An infected giant wasp from the depths of a hive city. Roughly 1 meter in length. Strong mandibles and armor-like chitin. Able to fly at speeds upwards of 20 MPH. Possesses a stinger with powerful venom.
-Puppet: A deceased Altered that has been taken over completely by Tide. Flood biomass has increased greatly within these individuals to take up most of their total biomass. While they usually only utilize a fraction of their true strength to remain unnoticed, Puppets are capable of enormous feats of strength on par with any combat form. Similarly, in terms of endurance they are much more capable of taking what would be lethal damage on an ordinary human and continuing to function at full or near-full capability. Each Puppet is capable of independent action depending on the memories imprinted onto them by Tide.
-Combat Boy: An Ork boy that has been infected. Fast, strong, durable, low intelligence. Surprisingly durable. Unable to use Ork Tek that relies on WAAAGH! energy to function, but able to wield most basic tools or mutate natural weapons.
-Combat Grot: A gretchin that has been infected. Small and nimble. Strong enough to kill a boy if it gets its whip-like arms around the Ork's neck, but not much more than an annoyance otherwise on its lonesome. Operates best in packs as disposable fodder. Sometimes rides Combat Squigs into battle.
-Combat Nob: An Ork Nob that has been infected. Large, slower than the boy, but much stronger and tougher. Higher combat intelligence than a boy or grot. Make capable shock troops.
-Combat Squig: An infected squig. Two tentacles sprout from its maw to drag prey inside or latch onto other objects and pull the squig forward with enough force to launch it clear through the air. Its maw is capable of opening even wider than an ordinary squig's.
Pure Forms
-Shifter: The 'standard' Pure Form. Capable of mutating into any forms it has sufficient biomass for. Most commonly used to create a Tank form, two Ranged forms, or two Stalker forms.
-Worm: Its a worm. Able to burrow. Can squeeze things to death.
-Elite: Based off the Sangheili from Halo, but physically faster and stronger than what a Sangheili would be capable of. Not incapable of mutation, but rarely does so since its meant as a type of Puppet.
Flood Tech Forms
-Barbarian: Similar to the Tank form in appearance, but with two sets of claws instead of the normal one. These claws are partially metal and electrified. Very strong and durable. Little armor, with plating mostly being fused around the vital organs.
-Fighter: Similar in appearance to a more human ogryn. Not unlike a Space Marine in terms of physical stature at two and a half meters and surpassing the average space marine in strength, though lacking in comparison when it comes to dexterity and combat intelligence. Most of its armor is fused around the vital organs. Wields a Gravity Hammer.
-Rogue: Looks sort of like a small human, around one meter tall. Lacks armor. Equipped with anti-grav tech that allows it to leap farther and move faster. Extremely fast and nimble. Wields a laspistol that is mostly just there for the utility. Meant mostly for scouting and similar acts of skullduggery rather than actual combat.
-Ranger: An Elite equipped with Flood Tech weapons. Its armor is little more than ceramite plates wrought in a specific manner, but it remains fairly effective against kinetics. Wields an Elite Chain Blade and modified Plasma Gun.
Flood Tech Weapons
-Gravity Hammer: A hammer equipped with enhanced gravitic technology commonly found in servo skulls. Interlaced with neural pathways, connecting it to its wielder on a mental level. The first step of the hammer fall is to draw the target towards the hammer by increasing gravitational pull. The second is to increase damage by reversing the gravitic pull just as the hammer connects. Effects in the early stages are... mediocre, with most of the damage being owed to the raw strength of the Fighter form.
-Elite Chain Blade: A chain blade fashioned in the likeness of the Elite Energy Blades from Halo.
-Electrified Claws: Simple metal claws that have a strong electric current running through them. The effects of this electricity are... debatable, as most things that come in contact with the claws are already moments away from death owing to the fact that they are within arms reach of a Barbarian form. Provides no benefit against armor, save for the possible transmission of electricity to the wearer.
Mind Forms
Note: Mind Forms is another term for key minds, which were retconned into creation from and should not be confused with the Keymind, the next level of evolution of the Gravemind.
-Proto-Gravemind (Slug): A Slug shaped Proto-Gravemind. Not very fast, able to move at a slow walking pace.
-Proto-Gravemind (Defense): A Proto-Gravemind with two whip-like tentacles for defense.
-Gravemind: A fully formed Gravemind consisting of biomass equivalent to over ten thousand corpses. Hyper intelligent. Range of Flood control extends across an entire solar system, at minimum. Current Gravemind is based off the same Gravemind from Halo 2 Anniversary Edition.
Other
-Altered Human: A human that has been infected by the Flood but not transformed or taken control of by it. Possesses greater than average strength and dexterity. Ability to heal and immune system has been taken over entirely by the Flood. Certain organs may be replaced by Flood-variants. Indistinguishable from a normal human except through an in-depth medical exam. At any given time, the Flood can immediately take control of the body from the brain, chemically isolating it. If desired, the Flood can transform the body into a combat form within seconds. The Flood can look through and edit the memories of the Altered at-will. Lungs are replaced with Flood-variants which naturally release Flood Spores into the air through exhaling. When asleep, the Altered dream of the Flood.
-Infector Pod: The standard and swiftest method of infection. A single Infector Pod can transform a human into a combat form in a matter of seconds. Not very strong and easily slain by anyone with a crowbar, but ingesting even the slightest amount of its biomass will result in infection.
-Flood Spore: One single Flood Spore can destroy a species. While much slower than the Infector Pod, being infected by a Spore can easily be said to be the worse fate. It takes several days for a single Flood Spore to transform the host, with changes coming faster as its growth accelerates. A Flood Spore is a micro-organism and cannot be seen by the naked eye. If uncoordinated, the Flood Spore will attempt to become a combat form and infect others, spreading the Flood until a Proto-Gravemind can be formed. If coordinated, the Flood Spore can be directed in certain directions such as the creation of combat forms or the much subtler Altered.