Counter Strike Online Wiki

For the original version, see UMP45.

SKULL-3 is a submachine gun of the SKULL series built by the Government in Counter-Strike Online based on the UMP45.


The SKULL-3 is an anti-zombie submachine gun chambered with 35 rounds of .45 Anti-Zombie cartridge and is capable of being dual-wielded. When being dual-wielded, it fires 70 rounds of .45 Anti-Zombie cartridge. This weapon is also equipped with a nondetachable suppressor, foregrip, extended magazine (+10 magazine capacity compared to the UMP) and a usable scope single mode.

Details: Press the main weapon key (default: 1) to select the mode. Switch modes by clicking.
Single Mode Dual mode
  • Low recoil
  • Light weight
  • Short reload time
  • Usable scope
  • Good accuracy in long range
  • High damage against both humans and zombies
  • High rate of fire
  • Silent firing sound
  • Can penetrate up to 4 objects
  • High stun to zombies
  • High reserved ammo
  • Low damage and magazine capacity
  • Very heavy
  • Unusable scope
  • Longer reload time
  • High recoil
  • Easily runs dry
  • Expensive price
  • Low knockback power

Release date[]

  • South Korea: 12 January 2012.
  • Taiwan/Hong Kong: 17 January 2012.
  • China: 18 January 2012.
  • Japan: 22 February 2012.
  • Indonesia: 12 September 2012.
  • Singapore/Malaysia: 7 November 2012.
  • Turkey: 14 May 2014.
  • CSN:Z: 23 September 2014.
  • Vietnam: 26 March 2015.


Mode A mode (0m) B mode (0m)
Armor Yes No Yes No
Head 81 100+ 105 100+
Chest 20 28 26 35
Gut 20 28 26 35
Leg 20 21 26 26
Mode Buy cost Ammo cost Total
Original $4000 $1050 $5050
Scenario $4000 $3000 $7000
  • When dual-wielded:
    • The rate of fire is higher than most submachine guns.
    • The weight is lower than M134 Minigun.
    • It has similar reload style as the Dual MP7A1's.
    • The accuracy is same as the MG3,
    • The recoil is slightly higher than the MG3.

  • Original: Not recommended as it could waste the user's money.
  • Deathmatch/Team Deathmatch/Basic: Recommended due its fair damage, accuracy, low recoil, high rate of fire, light weight and usable scope in single mode.
  • Use dual mode in close combat as it has high damage and very high rate of fire.
  • Use single mode to engage enemies in medium to long range combat.
  • Try to fire in 3-rounds burst to maintain a good accuracy.

  • 35 rounds of A mode can deal 700 ~ 2800 damage, while 70 rounds of B mode can deal 1960 ~ 7840 damage to zombies.
  • Combine B mode with Deadly Shot for maximum damage output.
  • Use A mode to efficiently escape from zombies or as backup when using a melee weapon; use B mode to kill zombies.
  • Take note that B mode is not suitable to engage zombies in open areas due to it's heavy weight. Instead, use melee weapons such as the Skull-9 or Nata Knife to kill zombies while using A mode to stun or escape from zombies.
  • However, if the user has reached a safe human camp such as the ducts, it is recommended to switch to B mode as it has high damage and very high rate of fire.
  • SKULL-3 can kill a host zombie easily due to its high damage and very high rate of fire when using B mode.
  • Fire SKULL-3 in bursts for both modes to conserve ammunition.
  • A mode has really low recoil and very high stun power, enabling the user to fire accurately while running. Also, the zombie is hardly move when shot due to high stun power.

  • Using B mode on barricades help players to gain money faster. Furthermore, its very high rate of fire favors in destroying barricades efficiently.
  • Recommended when dealing with mini-bosses. However, the player needs proper skills to dodge their attacks.
  • Use B mode to handle large amount of zombies because it has high damage and very high rate of fire.
  • 70 rounds of SKULL-3 in B mode can deal around 10,000 ~ 17,000 damages to Bosses, noted that attack power has been maxed.

  • It can kill the Titan easily due to its high damage and very high rate of fire.
  • It can also be used to destroy barriers very quickly.
  • SKULL-3 is also good in dealing with bosses.

  • Tactics facing SKULL-3 users[]


    • SKULL-3 users are fast, mobile, silent and deadly if the users are experienced.
    • With B mode, they can annihilate your whole team easily with 70 rounds.
    • Sniper rifles and far-middle ranged weapon are recommended, don't try to approach them directly unless you have good skills.

    Zombie mods[]

    • Usually, SKULL-3 users will go with B mode, so they're deadly but slow in movement. If they're not in ducts, infect them quickly, especially when they are reloading in B mode.
    • With Deadly Shot, SKULL-3 in B mode can take down several <6000 HP zombies in ducts.
    • Light type zombies are recommended when dealing with SKULL-3 users.
    • SKULL-3 has high stun (nearly the same with MP5) and low knockback power.
    • Try not to engage SKULL-3 users alone, especially if they use the Deadly Shot skill.



    • Gerard: Gerard is seen arming with an SKULL-3 in a promotion poster.


    • Higher damage (+1)
    • Higher fire rate (+1%)
    • More accurate (+7%)
    • Higher clip size (+10)
    • Higher reserve ammo (+100)
    • Has zoom ability
    • Can be switched to dual mode
    • High penetration power
    • Shorter reload time (-1.0 second)
    • Silenced
    • Higher recoil (+2%)
    • Heavier (+2% weight)
    • More expensive (+$2300)
    • More expensive ammunition cost

    • Higher firepower (+5)
    • Higher rate of fire (+2%)
    • Higher magazine size (+20)
    • Silenced
    • Less accurate (-3%)
    • Heavier (+26% weight)
    • More expensive (+$2000)
    • Higher recoil (+10%)

    • Higher damage (+3%)
    • Higher accuracy (+3%)
    • Higher stun power
    • Higher magazine size (+5)
    • Cheaper
    • Silenced
    • Same knockback
    • Usable scope
    • Same reload time (2.5 seconds)
    • Higher recoil (+1%)
    • Lower rate of fire
    • Heavier (+2% speed reduction)
    • Has no Balrog Charging System
    • More expensive ammunition


    Firing sound

    Bolt pulling sound (unused)

    Reloading sound

    Drawing sound


    • The word "SKULL-3" can be seen on the weapon.
    • The wielder's running speed will increase when the dual-wielded SKULL-3 are thrown away during their reload animations. The reverse happens with the M134 Minigun.
    • Earlier version of SKULL-3 had the ammo costs only $35 per 35 bullets.
    • An exploit exists whereby the user will automatically reload the weapon upon switching between A and B modes.
    • Despite the scope being obstructed by its cap, it can still be used in A mode.
      • The scope has the words Aopoint on the side, a parody of the real-world company Aimpoint.
    • Oddly, in B mode it's heavier compared to SKULL-4, despite it being a submachine gun.