Skills

**Skills** (スキル, *Sukiru*) are abilities that a player can use in a game.

## In Sword Art Online

### Leveling

In Sword Art Online, skills can be leveled up to increase the effects of the skills, as well as unlock mods and new abilities. Skill levels are independent of player levels. A skill's level is increased via usage of the skill.

### Skill Slots

In general, skills must be equipped in a limited amount of skill slots. Players are given two initial slots, with a third slot granted at level six, a fourth one granted at level twelve, a fifth on level twenty, and an additional slot every ten levels afterwards. Skills may be trained up to level 1,000, at which it is considered **Completed** (完全習得, *コンプリート*), *Konpurīto*). If a skill is removed from its slot, its proficiency is reset to zero, unless a special item is used to store the skill. It is rumored that there is an almost unlimited number of skills in Sword Art Online.

### Types

There are various types of skills in Sword Art Online, including Support Skills, Combat Skills, Weapon Skills. Certain rare skills are also known as Extra Skills or Unique Skills depending on their rarity. Weapon Skills also unlock the use of special, system-assisted weapon techniques known as Sword Skills. Players have also dubbed some of their techniques as Outside System Skills, though they are not actual skills system-wise.

### Mods

Certain skills in Sword Art Online also have **Mods** (モッド, *Moddo*). Mods can either be special bonuses that increase the effectiveness of the skill (e.g. decreasing Sword Skill cooldown time, increasing the range of the player's detection etc.), or various abilities (e.g. the Tracking mod for the Searching skill). It is known that at least for certain skills, for example, the One-Handed Sword, a new mod can be chosen every fifty levels of proficiency.

### Composition

**Composition** (コンポジション, *Konpojishon*) or **composite effect** (コンポジット効果, *Konpojitto Kouka*) refers to the combined effect produced with multiple skills. A composite effect is unlocked when two or more compatible skills reach a certain level. For combat skills, a composite effect may result in unlocking a new Sword Skill that makes use of two weapon types. Certain crafting and life skills may also have composite effects. The various compositions available in the game are not listed by the system, thus players have to discover them themselves.

#### Known Compositions

 Polearm Weapon Creation  One-Handed Weapon Creation
 Cooking  Mixing
 Carpentry  Sewing
 Carpentry  Sewing  Polearm Weapon Creation
 Tracking  Appraisal

### Weapon Skills

In Sword Art Online, there are several different classes of Weapon Skills, each of which unlocks the use of Sword Skills in that category. There are generic weapon skills such as One-Handed Sword and One-Handed Curved Sword. Then, there are additional weapon skills that can be unlocked after fulfilling a certain set of conditions. For example, in the sword category, the One-Handed Sword skill must be trained quite a bit before Rapier and Two-Handed Sword appears on the weapon skills list.

Weapon skills that do not have clear conditions for appearing are called Extra Skills. There are roughly around ten known Extra Skills, including the Katana skill wielded by Klein. Each of these extra skills have at least ten users of the skill.

There are ten Unique Skills, which are weapon skills unique to a single player. So far only six of them have been revealed and only two of them are known to be acquired by a player. Additional Unique Skills were intended to be released beginning with the 90th Floor of Aincrad.