Corrupt

Corrupt exists because of a mistake. On December 29, 2014, a code error in the Murder Mystery 2 scripts caused the Data Loss Glitch: about 50 players lost their items and recent data. After fixing it, the developer Nikilis gifted those victims an extremely rare knife as an apology, and that knife became Corrupt. The wiki guesses the name nods to the corrupted data.

First of its kind

It was the first unique weapon ever, although the category was first called Reward before being renamed Unique. It is also the only tradable unique weapon. The blade is golden with faint vintage engravings near the heel, a silver guard and a grayish-black handle, and it shares its mesh with the Default Knife. The statue of Nikilis on the lobby fountain holds it.

Rare, then not

Corrupt was the second rarest knife, behind Nik's Scythe, until The Duping Glitch of 2017. The wiki says only around 63 players allegedly owned it between 2015 and 2017, while thousands of copies exist now. Owning more than 20 copies gets the account banned on rejoining, and a known glitch requires resetting your character before it shows in the inventory. It partners with the godly gun Luger as the Corrupt Set.