Corrupt

In the main lobby, the statue of Nikilis on the water fountain can be seen holding this knife.

This knife was one of the main targets of The Duping Glitch of 2017, and lost a massive amount of value after the event.

This knife was the first unique weapon to ever exist, although this category was initially named "Reward" before being changed to "Unique" following an update later.

It is the only weapon with a rarity above Legendary that has the same mesh as the Default Knife.

This is the only tradable unique weapon.

Owning more than 20 Corrupts will result in the owner's account being banned upon rejoining the game.

There is also a glitch with Corrupt where you must reset your character before finally obtaining it in your inventory, and it's also the same way around when you trade away a Corrupt.

Before it was mass duplicated, there were (allegedly) only around 63 players who owned this knife in 2015-2017. Now there are thousands of copies of it in the game.

It partners with the godly gun Luger, making the Corrupt Set.