Fierzaa is a developer mostly recognised for creating the game KAT (Knife Ability Test). She has become a significant figure in the Roblox PvP community due to her unique approach to gameplay and game design.
Overview[]
Fierzaa’s username is believed to be a combination of the developer Berezaa 
Berezaa is a notable creator or influencer verified by Roblox Corporation. Learn more. and the Dragon Ball villain Frieza. She is famously known for having changed her Roblox username over 343 times.
She owns or co-manages multiple alternate accounts, including:
She has been part of several Roblox groups:
- fiergames
- ONE STUDIO™
- Filthy Weebs
- Otaku (where she only holds the role of "weeb", but is not the owner)
Knife Ability Test (KAT)[]
KAT is Fierzaa’s most iconic game. Players spawn into maps equipped with a revolver and a knife. They can unlock various knife abilities, such as Deathbeam, Ghost Knife, and more
The knife abilities encourage diverse gameplay styles. Weapon textures are inspired by games like Team Fortress 2, Counter-Strike, and even anime/manga like Berserk. For example, the exclusive admin-only knife Dragon Slayer is based on Guts’ sword from Berserk and is not throwable.
Weapon textures were mostly created by:
- Nettimato
- Rastamypasta
- Some by Fierzaa herself
KAT was taken under review by Roblox on August 1st, 2025. Making it unplayable for the foreseeable future.
Other Games[]
In addition to KAT, Fierzaa developed:
Appearance in Murder Mystery 2[]
Fierzaa appears in the game Murder Mystery 2 on the Police Station map. Her avatar can be found in the shooting range alongside developers like:
- Loleris
Loleris is a notable creator or influencer verified by Roblox Corporation. Learn more. - TayMaster
- Prisman Prisman is a notable creator or influencer verified by Roblox Corporation. Learn more.
The inclusion was made by Nikilis as a tribute to developers of similar games at the time.
Inactivity[]
Fierzaa is currently inactive. She has not provided any official reason for no longer updating KAT, and she rarely logs into her Roblox account.
Account Compromise[]
In late 2018, Fierzaa’s account was briefly compromised by a user known as Hasan. It is believed that the attempt was made to steal her Limited items.
Public Stats (as of 2 May 2025)[]
- Roblox group members: 165,574
- Game visits: 1,468,716,051
- Game favourites: 4,296,002
Avatar[]
Fierzaa is frequently seen wearing a Blackvalk on her avatar.