bossraid

A term that seemingly originated from the ROBLOX permadeath game Rogue Lineage, defining a player who can take on a large number of other players alone. Can be used as a verb, or an adjective. Possibly the player version of "raidboss"

*A player playing the oni class kills 3 other guys while outnumbered 5 to 1*
Player 1: "Holy shit, that dude is bossraiding so hard right now!" (Verb)
Player 2: "What a bossraid oni!" (Adjective)

Demon

1. An evil mythological being
2. Someone who is menacingly good at something

1. The demon killed Joe and ate his soul.
2. Johnny is an absolute demon at running. He can guaranteed beat anyone here in a race.