Skill

Most Operators in Arknights have skills; strong, triggerable abilities that can aid them or other Operators offensively or defensively by enhancing their stats, modifying their functionality, or giving them new capabilities altogether.

Only 3★ Operators and above have skills; 1★ and 2★ Operators have no skills whatsoever.

• 3★ Operators only have a single skill that is available initially.
• 4★ and 5★ Operators have two skills; the first is available initially and the second is available once they are promoted to Elite 1.
  • An exception to this is Amiya, who has three skills, following the same mechanics as 6★ Operators (see below).
• 6★ Operators have three skills; the first is available initially, the second is available once they are promoted to Elite 1, and the third is available once they are promoted to Elite 2.

Operators with multiple skills can only choose one of them to be used at a given time, which is done from the Operator or squad menu.

Generally, the first skill is a generic skill shared across all Operators of the same class and/or branch, while the second and third skills are unique to each Operator and often act as core to the Operator's playstyle.

Usage

All skills cost SP (Skill Point) to use. Most skills start out with a number of SP when the unit is deployed, which is referred to as "initial SP" and denoted by a white chevron prior to the skill's (green) required SP value:

Skills are activated in two different ways, both of which requires it to be charged by having enough SP and valid target(s) to be present within the skill's range if it requires one:

• Auto Trigger skills are activated immediately.
  • Occasionally, a skill condition related to the skill's effect has to be met for the skill to be enabled.
    • For instance, skills that give an Operator a deployable item, such as a fully-stocked Trapmaster, Silence's Medical Drone or Shamare's Cursed Doll will remain at their maximum value without taking effect until the player uses that deployable. Once the player is eligible to acquire a new deployable, the skill will be used.
    • Flametail's Quick Intuition will not activate if Flametail still possesses the ability to dodge an attack from a previous cast of the skill, meaning that unless Flametail gets hit, she will not trigger any of the skill's effects, including its DP generation.
• Manual Trigger skills are activated on the player's command.
  • Manual trigger skills are also subject to the rules as above, however, they are often designed with such mechanics that they are more unlikely to occur. It is still possible, however, for a manual ability to be impossible to cast due to not meeting a certain condition.
    • Notoriously, Push Stroker/Hookmaster Specialists will not be able to shift enemies that are outside their range. If an enemy is blocked behind one such Operator's range, they will be in range for basic attacks, but not for skills. This is actually useful in certain complex stalling strategies, as using the skill will cancel the Operator's basic attack, resulting in them doing absolutely no damage.

Occasionally, Operators have passive skills that are active at all times and do not require the player's input to function, although some are context-sensitive.

Most skills last for a short duration, but some skills last for an unlimited duration (actually for sufficiently long duration to be functionally unlimited in any stage, see Trivia for details). Some skills, that have instantaneous effects or modify the next basic attack, are regarded to have unlimited duration despite effectively not having any.

Some skills can store multiple charges, which means that while the skill is immediately usable after it is charged, the Operator can still recover/restore SP for and store immediately available additional uses of the skill up to a limit. These skills can be either Auto or Manual, though they tend towards the former, and they tend to be exclusively instant effects.

There are some unique mechanics pertaining to skill usage:

Mechanic	Information
Ammunition	Instead of lasting for a limited time, the skill lasts for a number of attacks and can be deactivated at will.
Overcharge	(Known as Charged in-game) The skill can recover/restore additional SP after it is fully charged, up to twice the normal limit (e.g. a skill that costs 30 SP needs to have a total of 60 SP to be Overcharged). Should the skill be activated once Overcharged, it will have additional effects.
Overload	When the skill's remaining duration is at most half of the total duration, it will have additional effects and certain drawbacks.

SP recovery

SP can be recovered in three different ways:

• Automatic Recovery: Recovers SP every second.
• Offensive Recovery: Recovers SP each time the unit attacks (including healing for Medics).
• Defensive Recovery: Recovers SP each time the unit is attacked, even if the attack is dodged or resisted.

For each of these, the default amount of SP recovery is 1. This amount can be changed in a variety of ways.

Operators with "Skill Aura" talents can increase automatic SP recovery. If more than one operator with these talents are on the field, only the strongest effect applies to the relevant targets.

• Ptilopsis's talent "Skill Aura" increases the SP recovery rate for all automatic recovery skills.
• Mostima's talent "Skill Aura - Caster" increases the SP recovery rate for casters' automatic recovery skills.
• Suzuran's talent "Skill Aura - Supporter" increases the SP recovery rate for supporters' automatic recovery skills.

Some operators can restore the SP of other friendly units:

• Ch'en's talent "Scolding" periodically restores the SP of all offensive recovery and defensive recovery skills.
• Warfarin's talent "Blood Sample Recycle" restores the SP of Warfarin herself and a random ally in her range whenever an enemy unit dies within her range.
• Saria's talent "Refreshment" and Hung's Medical Mode Countermeasure the SP of Operators that they heal.
• Stainless's devices when he equips Efficient Resupply restores the SP of the target Operator(s).
• Windflit's Machine Rapport restores the SP of the Operator(s) targeted by his Support Devices.

A few methods combine two or more of the SP recovery types:

• Certain collectibles in Integrated Strategies can periodically grant SP to skills with offensive or defensive recovery or increase the rate for skills with automatic recovery. These stack with other methods of SP generation.
• Amiya's talent "Emotional Absorption" adds offensive recovery to her skills' automatic recovery.
• Blemishine's talent "Sword and Shield" adds offensive recovery to all skills with defensive recovery.

SP debuffs from challenge mode/adverse environment conditions or CC contracts may increase the amount of SP required to activate skills or slow the rate at which automatic recovery SP is generated. Effects that slow SP generation can be listed as either a direct reduction to SP generation (e.g. -0.1 SP/s), or as a percentage (e.g. -10%). In either case, the effect is applied to the base SP generation rate of 1 SP/s, and other effects (e.g. Ptilopsis's talent) apply additively.

Necrosis Damage prevents the victim from using their skill and causes them to lose 1 SP every second for 15 seconds (unless the skill is already active) after it procs.

SP Lockout

SP Lockout is the term used for the time an operator cannot gain any SP in any way. This includes direct SP granting like Saria's Refreshment talent or the Portable Supply Station (even though it is still depicted in the case of the latter, but there is no actual effect) as well as passive SP granting like Ptilopsis' Skill Aura talent. Operators who have Offensive or Defensive Recovery on their skill can still gain SP in a direct way, but will not benefit from passive SP generation.

Operators enter SP Lockout when:

• Their Manual Trigger skill is not activated. This is signified by a full green skill bar.
• Their Automatic Trigger skill is on, but is not activated due to there being no enemies within range (or in the case of Medics, no operators to heal). This is signified by an orange skill bar. An example case is Honeyberry's Spiritual Care.
• Their skill bar is in the process of depletion. This is signified by a depleting orange skill bar. For skills that are defined as an 'Instant Attack', this moment is the moment when the skill activates.
  • Saria and Hung cannot grant themselves SP due to this type of lockout.
• Their skill is a passive effect. This is signified by a transparent skill bar. Example cases are Hoshiguma's Thorns and Manticore's Scorpion Venom
• Their skill is the generation of a Summon, but the summon is not deployed yet. This is signified by a transparent skill bar. Example cases are Silence's Medical Drone and Shamare's Cursed Doll.
• Their skill has finished charging and has an infinite duration. This is signified by an orange skill bar. Example cases are Thorns' Destreza and Skadi the Corrupting Heart's Wish of Burial Beyond the Light.
• Their skill has Ammunition and is turned on. This is signified by an orange skill bar that has vertical divisions representing the amount of ammo currently in possession. An example case is Aurora's Artificial Snowfall.
• Their skill has a maximum amount of uses within battle, and that maximum is reached. This is signified by a transparent skill bar. Example cases are Sussurro's Deep Healing and Guard Amiya's Ying Xiao - Shadowless.

The only operator truly capable of bypassing SP Lockout is Siege, due to her Crushing talent which is made to synergize with her skill Aerial Hammer. Operators who can Overcharge their skills can only bypass this state once, and they still enter it once their skill is finished Overcharging accordingly. Operators whose skill consists of an Instant Attack that can hold charges (i.e Ifrit's Pyroclasm) have no meaningful SP Lockout time, allowing effects like the Hand of Diffusion to work on an effectively continuous rate.

Operators who are affected by any of the bottom four causes mentioned cannot be forced out of SP Lockout without intervention of the player or from enemies that appear in the operator's range. For example, W will not place a Front Toward Enemy if there are no available tiles within her range to place them on, and one will not be able to activate Leonhardt's Deconstruct and Detonate if there are no enemies within his range.

Upgrades

Skills can be upgraded by leveling them from the Skill Upgrade menu on each Operator's Character Details page. Skills can be upgraded through 7 levels, and all of the Operator's skills (in case they have more than one skill) will be upgraded at the same time.

Upgrading skills require the following:

Level	Skl. Sum.	Material(s)	Requirement(s)
	1	–	–
	2	Few T1 upgrade materials
	1	Few T2 upgrade materials
		Few T3 upgrade materials	Promoted to Elite 1
	2

Level	Skl. Sum.	Material(s)	Requirement(s)
	2	–	–
		Some/few T1 upgrade materials
	3	Some/few T2 upgrade materials
			Promoted to Elite 1
		Some/few T3 upgrade materials
	4

Level	Skl. Sum.	Material(s)	Requirement(s)
	4	–	–
		Some T1 upgrade materials
	6	Some T2 upgrade materials
			Promoted to Elite 1
		Some T3 upgrade materials
	6

Level	Skl. Sum.	Material(s)	Requirement(s)
	5	–	–
		Many T1 upgrade materials
	8	Many T2 upgrade materials
			Promoted to Elite 1
		Many T3 upgrade materials
	8

Mastery

Once the Operator's skills are at Level 7, they can be further improved to three additional levels through the Mastery (also known as Specialization) training function. Only 4★ Operators and above that have been promoted to Elite 2 can undergo Mastery training.

Mastery training is done at the Training Room of the RIIC. The process takes time to complete (which can be accelerated by assigning certain Operators as trainers), and unlike skill upgrades, are done individually for each skill.

Mastery trainings require the following:

Level	Skl. Sum.	Materials	Time	Requirements
	2	Some/few T4 and T3 upgrade materials	8 hours	Level 1 Training Room
	4	Some T4 upgrade materials	16 hours	Level 2 Training Room
	6	Some/few T5 and T4 upgrade materials	24 hours	Level 3 Training Room

Level	Skl. Sum.	Materials	Time	Requirements
	5	Some T4 and T3 upgrade materials	8 hours	Level 1 Training Room
	6	Many/some T4 upgrade materials	16 hours	Level 2 Training Room
	10	Some T5 and T4 upgrade materials	24 hours	Level 3 Training Room

Level	Skl. Sum.	Materials	Time	Requirements
	8	Many/some T4 and T3 upgrade materials	8 hours	Level 1 Training Room
	12	Many T4 upgrade materials	16 hours	Level 2 Training Room
	15	Many/some T5 and T4 upgrade materials	24 hours	Level 3 Training Room

Tips

• Mastery training is very resource- and time-consuming, especially for 6★ Operators. Thus it is important to know how significant the boost to the skill will be and whether or not it is worth farming the materials for.

Trivia

• Skills with "unlimited" duration actually last for up to 60 minutes (30 if the game speed is doubled); however, the skill will almost never be deactivated during any operation as it greatly outlasts the average operation time.
  • Furthermore, the skill ending rarely has any effect, as these skills are programmed to permanently update the Operator's status with the effects of the skill once turned on. They will still receive SP as normal, and can be enabled a second time once they initially end, but it will typically have no effect, unless the skill has an instant, immediate activation effect. For instance, activating a Command Terminal will not result in any change to its additional defensive buffs, but it will increase the deployment limit every time it is activated.
• Even though 1★ and 2★ operators have voice lines for skill activation, they can never be heard during operations, due to their lack of skills.
• As pointed out with the Command Terminal above, non-Operator deployable units and static units pre-placed in the level, both of which are known internally as "tokens" also use skills.
  • Most enemy units, as well as environmental mechanics (that are controlled by invisible static units) like High Tide and the Londinium Secondary Defense Artillery use skills as well, although they are typically invisible from the player unless in specific cases like the Defense Artillery or the Sui-xiang's Omnidirectional Breath that clearly display an SP gauge, or Ishar'mla, Heart of Corruption, who openly displays the SP acquired as flyover text.
  • That means most enemy ability timers are based in the same system of SP with different means of acquiring it (every hit/every second). The major difference, of course, is that enemy units can have several skills at once.