The Balrog series is the second anti-zombie weapon series to be featured in Counter-Strike Online after the famous Skull series. However, unlike the weapons from the Skull series which were developed by the Rex Research Institute, the weapons from the Balrog series were developed by the newly formed Aegis Institute with the same purpose of combating zombies. It should be known that Aegis Institute has also engineered a third anti-zombie weapon series known as the Janus series.
The weapons from the Balrog series deal fatal damage to enemies with the unique technology implemented into them. Given the name "BALROG Charging System", the weapons are known to cause explosions and an increase in damage after continuous firing. This new system is also incompatible with the original Skull series. Along with the weapon's technology, Aegis Institute had also created a new 'specialized' type of ammunition to rival that of the Skull series' AZ ammunition. It is the Balrog series' AHE (Aegis High-Explosive) ammunition.
So far, there are 6 weapons in the Balrog series:
- Main article: Balrog-I.
Balrog-I is a pistol chambered with 10 rounds of .50AE AHE and does high damage for a pistol. The equipped BALROG Charging System is a manually pumped grenade launcher that inflicts an afterburn effect on enemies.
- Main Article: Balrog-III.
Balrog-III is a submachine gun based on the H&K MP5K PDW and is equipped with the Balrog Charging System. It is fed with 30 rounds of 9mm AHE. It is equipped with a reflex sight for long range engagement.
- Main Article: Balrog-V.
Balrog-V is an assault rifle based on the H&K G36C in Counter Strike Online and is equipped with the Balrog Charging System. It is fed with 40 rounds of 5.56mm AHE. It is equipped with a holographic sight for long range engagement.
- Main article: Balrog-VII.
Balrog-VII is a machine gun based on the M60E4 and is equipped with the Balrog Charging System. It is chambered with 120 rounds of 7.62mm AHE. It is equipped with a usable scope for long range engagement.
- Main Article: Balrog-IX.
Balrog-IX are dual-wielded gauntlets and is equipped with the Balrog Charging System. It has low attack range but does fatal damage to zombies. It is able to inflict explosive damage with its secondary attack and inflicts medium knock-back power.
- This is the first Anti-Zombie weapon series to feature explosive rounds.
- These weapons possess red, black and white color patterns.
- These weapons can penetrate up to 2 objects except for Balrog-III and Balrog-XI.
- All weapons from this series feature a crafted Balrog figure attached to them.
- Indonesia region will not resell Balrog-VII, III and I.