So... I was doing runs in Dark Forest when my screen suddenly flashed white! Suddenly, Two NPC's by the name of Bronx and Bomber came in! They killed everything in sight, it was like they were invincible! Once the King of The Forest was killed my screen flashed white again and then the System said:

Silentarrowszz has recieved the Bronxbomber! Congratulations!
So... Is this the normal way that people recieve their Bronxbombers? Or am I the first to recieve it this way?