Stun

“	Unable to move, block, attack, or use skills.	”
	—In-game tip

Stun is an Abnormal Status in Arknights.

Effect

A stunned unit is indicated by a "dizzy" effect above them, with Operators and certain enemies (notably Mephisto and W) having a special animation used when they are stunned. In this state, the unit will become unable to perform any actions, be it attacking, moving, or using skills. Friendly units that are stunned may still be retreated.

One should watch out if a friendly unit is stunned, as they will become unable to block enemies. This can be dangerous if the said friendly are frontline Operators, as this will allow enemies to move past them.

Sources

Against enemies

Operators

Operator	Source	Range/Target	Duration
Aak	Drug Cocktail Administration (talent)	Attack (randomly)	0.6 ~ 1 second(s)
Ambriel	Precise Strike (talent)	Attack (with a 25% (+3%) chance, only against enemies outside the normal attack range)	2 seconds
Ash	Auxiliary Equipment (talent)	Within attack range, AoE	3/4 seconds
Beeswax	Guardian Obelisk	Sand Obelisk deployment 　□□□　 　□■□　 　□□□	L1-L6: 1 second L7: 1.5 seconds M1: 2 seconds M2: 2.5 seconds M3: 3 seconds
Bibeak	Blade Swap	Up to 5 enemies 　□□　　　 　■□□□　 　□□	L1-L3: 0.8 seconds L4-L6: 1 second L7: 1.2 seconds M1: 1.4 seconds M2: 1.6 seconds M3: 1.8 seconds
Blitz	Flash Shield	□□　 　■□□　 　　□□	L1-L3: 2.5 seconds L4-L6: 3 seconds L7: 3.5 seconds M1: 3.8 seconds M2: 4.1 seconds M3: 4.5 seconds
	Shield Bash	Blocked enemies	L1-L6: 5 seconds L7-M2: 6 seconds M3: 7 seconds
Ch'en	Sheathed Strike	Attack (when charged)	L1-L3: 1 second L4-L6: 1.25 seconds L7-M3: 1.5 seconds
	Chi Xiao - Shadowless	Last hit 　　□　　 　□□□　 □□■□□ 　□□□　 　　□	L1-L3: 2 seconds L4-L6: 2.5 seconds L7-M2: 3 seconds M3: 4 seconds
Click	Synchronized Attack	Attack, both Click herself and her Drone (with a 20% ~ 27% chance while active) 　□□□□　 　■□□□　 　□□□□	L1-L6: 0.4 seconds L7-M2: 0.7 seconds M3: 1 second
Cliffheart	Binding Chains	Up to 2/3 enemies 　　□□□　 　■□□□　 　　□□□	L1-L7: 1.5 seconds M1: 2 seconds M2: 2.5 seconds M3: 3 seconds
Croissant	Magnetic Hammer	□　　 　□■□　 　　□	L1-L3: 2.5 seconds L4-L6: 3 seconds L7-M2: 3.5 seconds M3: 4 seconds
Eunectes	Menacing Slash	Blocked enemy	Menacing Slash's remaining duration
Flametail	"Pinus Sylvestris"	Applied twice 　　□　　 　□□□　 □□■□□ 　□□□　 　　□	0.5 seconds
Frost	Trap Deployment	Welcome Mat trigger	L1-L7: 1 second M1-M2: 1.2 seconds M3: 1.5 seconds
Glaucus	Counter EMP	Only works on drones 　　　□　　　 　　□□□　　 　□□□□□　 □□□■□□□ 　□□□□□　 　　□□□　　 　　　□	L1-L3: 3.5 seconds L4-L6: 4 second L7: 4.5 seconds M1: 5 seconds M2: 5.5 seconds M3: 6 seconds
Gummy	Frying Pan Specialist (talent)	Attack (with a 10%/15% chance)	0.5/1 second(s)
Kal'tsit	Non-Damaging Restructuring (talent)	When Mon3tr is knocked out (not retreated) 　□□□　 　□■□　 　□□□	3 (+0.5) seconds
Liskarm	Counter Arc	Attack (with a 10% ~ 25% chance while active) to up to 3/4 enemies	1 second
Manticore	Toxic Overload	Attack (while active)	L1-L3: 0.5 seconds L4-L6: 0.6 seconds L7: 0.7 seconds M1: 0.8 seconds M2: 0.9 seconds M3: 1 second
May	Binding Shock	Attack (with a 30% chance while active)	L1-L3: 0.9 seconds L4-L7: 1 second M1-M2: 1.1 seconds M3: 1.2 seconds
Mizuki	Moon in the Water	Attack (while active) □□□　　 □□□□　 □■□□□ □□□□　 □□□	L1-L3: 0.5 seconds L4-M6: 0.7 seconds L7-M3: 1 second
Mostima	Lock of Shattered Time	All enemies within attack range	L1-L3: 4 seconds L4-L6: 5 seconds L7-M2: 6 seconds M3: 7 seconds
Mr. Nothing	Unexpected Strike (talent)	Attack (after not attacking for 4 seconds)	3/4 seconds
Mudrock	Crag Splitter	Attack (with a 30% chance when charged) 　□□□　 　□■□　 　□□□	L1-L3: 0.4 seconds L4-L6: 0.5 seconds L7: 0.6 seconds M1: 0.8 seconds M2: 1 second M3: 1.2 seconds
	Bloodline of Desecrated Earth	□　　 　□□□　 □□■□□ 　□□□　 　　□	After the first phase ends L1-L6: 3 seconds L7: 3.5 seconds M1: 4 seconds M2: 4.5 seconds M3: 5 seconds
Nearl the Radiant Knight	Blazing Sun's Obeisance	Blazing Sun deployment 　　□　　 　□■□　 　　□	3 seconds
	Brave the Darkness (talent)	When deployed 　　□　　 　□■□　 　　□	E1: 2 seconds E2: 3 seconds
Phantom	Night Raid	□□□　 　□■□　 　□□□	L1-L3: 2 seconds L4-L6: 2.5 seconds L7: 3 seconds M1: 3.5 seconds M2: 4 seconds M3: 4.5 seconds
Rosmontis	Nociceptor Inhibition	Attack (with a 20% chance while active)	L1-L3: 0.7 seconds L4-L6: 0.9 seconds L7: 1.1 seconds M1: 1.2 seconds M2: 1.3 seconds M3: 1.5 seconds
	"As You Wish"	Tactical Equipment deployment 　□□□　 　□■□　 　□□□	L1-L3: 1.5 seconds L4-L6: 2 seconds L7-M2: 2.5 seconds M3: 3 seconds
Siege	Skull Breaker	Attack (with a 40% chance while active)	L1-L3: 0.5 seconds L4-L6: 0.8 seconds L7: 1.1 seconds M1: 1.2 seconds M2: 1.3 seconds M3: 1.5 seconds
Skyfire	Fire of Heaven	Attack (while active)	L1-L3: 0.1 seconds L4-L6: 0.15 seconds L7: 0.2 seconds M1: 0.4 seconds M2: 0.6 seconds M3: 1 second
Texas	Sword Rain	Applied twice 　　□　　 　□□□　 □□■□□ 　□□□　 　　□	L1-L7: 2 seconds M1-M3: 3 seconds
Tomimi	Gavial's Protection Plan	Attack (randomly, with a 50% ~ 100% chance while active) 　　□　　　 　　■□　　 　　□	L1-L3: 0.6 seconds L4-L6: 0.8 seconds L7-M2: 1.2 seconds M3: 1.6 seconds
W	King of Heart	Within attack range, AoE	L1-L3: 1.5 seconds L4-L6: 1.8 seconds L7: 2.1 seconds M1: 2.4 seconds M2: 2.7 seconds M3: 3 seconds
	Jack in the Box	Front Toward Enemy detonation	L1-L3: 1.4 seconds L4-L6: 1.6 seconds L7-M1: 1.8 seconds M2: 2 seconds M3: 2.2 seconds
	D12	Up to 3/4 enemies within attack range, AoE	L1-L3: 3 seconds L4-L6: 3.5 seconds L7-M1: 4 seconds M2: 4.5 seconds M3: 5 seconds
Weedy	Barrel Burst	Attack (when charged)	L1-L6: 0.8 seconds L7: 0.9 seconds M1: 1 second M2: 1.1 seconds M3: 1.2 seconds

Objects

• Imprisonment Devices stun enemies in its AoE for 2 seconds.
• Mr. Booms' Ill Temper stun enemies in the adjacent tiles for 12 seconds.
• Pulse Defense Modules on Multivariate Cooperation stuns enemies in its lower part's AoE for 7 seconds.
• Stun Generators' EMP Blast stun enemies in the surrounding tiles for 7 seconds (15 seconds for those in Pyrite Gorge).

Against friendlies

Operators

Operator	Source	Range/Target	Duration
Amiya	Spirit Burst	Self	10 seconds after Spirit Burst expires
Broca	High-Voltage Current		After High-Voltage Current expires L1-L3: 8 seconds L4-L6: 7 seconds L7-M2: 6 seconds M3: 5 seconds
Conviction	Genesis	Only if Genesis fails (50% chance, all friendlies within range) 　　□　　 　□□□　 □□■□□ 　□□□　 　　□	5 seconds
	Safe Landing (talent)	Self	10 seconds after deployment
Corroserum	Focus Overload		10 seconds after Focus Overload expires
Eunectes	Iron Will		5 seconds after Iron Will expires
Gitano	Destiny		After Destiny expires L1-L3: 15 seconds L4-L6: 14 seconds L7: 13 seconds M1: 12 seconds M2: 11 seconds M3: 10 seconds
Liskarm	Counter Arc		5 seconds after Counter Arc expires
Scene	Panoramic Overload	All deployed Buggy Cams	5 seconds after Panoramic Overload expires
Specter	Bone Fracture	Self	10 seconds after Bone Fracture expires

Enemies

Enemy	Method	Duration
Defense Crusher Defense Crusher Leader	Every three attacks	7 seconds
Dockworker Dockworker Leader	Every four attacks
Sniper	Every three attacks	5 seconds
Sniper Leader		15 seconds
"The Big Ugly Thing"	Death explosion (AoE, 3 tiles)	16 seconds (Level 0) 25 seconds (Level 1)
Lost Colossus	Boulder attack (range 2.5 tiles, 13 seconds cooldown)	25 seconds
Jesselton Williams	Every four attacks (up to 2 targets)	3 seconds
The Blood Knight Dikaiopolis	Exsanguination (global range, 10/15 seconds cooldown)	10 seconds

• The Lost Colossus will never use the boulder attack against stunned friendly units.

Other

• When Nervous Impairment procs, the victim will be stunned for 10 seconds.

Interactions

Operator	Skill/Talent	Notes
Ash	Assault Tactics	Ash's attacks while Assault Tactics is active deals 150% ~ 250% damage against stunned enemies.
Blitz	Shielded Shooting (talent)	Blitz attacks stunned enemies over the others and his ATK is increased to 130% ~ 160% (+5%) against stunned enemies, which is multiplied by 1.2× ~ 1.5× while  Shield Bash is active.
W	Insult to Injury (talent)	Stunned enemies within W's attack range takes +18% (+3%) Physical damage.

Trivia

• There are actually two flags in the game for the Stun status effect. The one in use in majority is the traditional "STUNNED" flag. There exists, however, an unused "STUNNED_NO_AMPLIFY_DAMAGE" flag which has the effect of traditional stun but does not apply the aforementioned damage amplifications in the Interactions section.