The Multitype (マルチタイプ) is the ability to summon, and control various types of energy. These energy types allowed the user to control elemental, physical, or psychological strengths to their own will. This ability was once one full ability held by Arceus, until after The Battle of Yin and Yang, which the Multitype had to be split up, and sent off to what's known as The Chose. Each type present among the Multitype has it's own special powers, strengths and weaknesses, which had gone down and scattered around to various individuals. There's also a 2nd version of these types that Giratina also possesses, otherwise known as 'Arke-types', which had suffered the same results.
The actual number of types evident in the Multitype are unclear, the ability having lost most of them soon after the battle. However, there are a total of 17 (Original and Arke-types in order of name) that had been split among various forms.
Mizu (水) - Uzu (渦)Edit
The Mizu is the power over water. The ability itself allows the user to control, and manipulate various forms of water to their own will, and battle with water-based weaponry, similar to Greninja's water ninja tools. The user is also more powerful underwater, able to stay underwater for longer periods of time, and swim much faster. The user though isn't really strong physically, and is vulnerable to electrical energy or liquid toxins.
Kasai (火災) - Netsu (熱)Edit
The Kasai is the power over heat. This ability is the more potentially destructive types, allowing the user to summon up from a single small flame, to a fire-storm. As well of a weapon Kasai can be, there isn't too much control of it once it's been unleashed, and the user's more at risk of self pain, or pain over allies. The user's also vulnerable to aquatic damage, and unable to activate in humid or freezing conditions.
Furaito (フライト) - Kaze (風)Edit
The Furaito is the power over the wind, able to allow the user to control the direction of the air currents. It gives the user heightened agility, and can control the wind to allow the user to move around much more rapidly and with better accuracy. This is one of the weakest of the types though when it comes to physical power, making the user more weaker to oncoming attacks.
Tatakai (戦い) - Sentō (戦闘)Edit
One of the more stronger types, the Tatakai is the mostly a strength enhancer, the user gaining a rapidly higher amount of strength, making the user almost inhumanly powerful. There's no exact limits to how much exact strength the user is given, depending on the user. However, the strength can sometimes have lack of control, causing damage and destruction due to accidents if not controlled.
Seishin-Tekina (精神的な) - Kokoro (心)Edit
Otherwise known as 'Sei', Seishin-Tekina is the given enhancement of the aura and mind. A rather mysterious type, it allows the user much more psychological enhancements, such as Telekinesis, Telepathy, or reading auras. Having such power over the mind, unfortunately, means that the user's physical strength is much weaker, and more prone to direct pain.
Chikyū (地球) - Iwa (岩)Edit
The Chikyū is the elemental power of the earth, the strong ability to shape the world the user lives in. The power allows the user to easily move around boulders, mountains and gravel to a degree to overpower any machine. This power, however, does follow a similar issue to water as Kasai, though not as deep. This makes the user unable to swim.
Shi (死) - Hametsu (破滅)Edit
A more ominous type, Shi is power relating to the undead. The power of the undead for the user, basically, turns them into either a demonic figure, or a grim reaper, depending what powers the user conjures. Few examples include raising undead servants, or manipulating shadows. This power doesn't have an exact weakness aside from light, which means the user will need to use it during night (new moon for the strongest).
Dendō (電動) - Inazuma (稲妻)Edit
The Dendō is power over Electricity, the user able to attack with electrical projection. The type's most renounced for its quality for MPH, the user given enhanced speed to go along with lightning. It is unclear of Dendō is its own type, or a sub power to Kasai, but the similarities (such as the destruction consequences) and differences (Dendō isn't weak to water) make it hard to tell. It is unable to harm any rubbery material or the earth, however.
This one in particular is a type only by Giratina soon after betrayal, power over darkness. It shares many similar properties to Shi, to the point where it can easily be mistaken for the other. The soul difference though is that Shi revolves around death, while Dāku revolves around pure evil, manipulating enemies by 'breaking them down' into submission.