comes from "merc" (pronounced "murk") short for mercenary.
To be killed, murdered, or otherwise mercilessly and overwhelmingly defeated or put down. (well executed and without struggle, the way a pro mercenary would do it.)
Became popular in early 2000's. Also spelled "merc", "merk", and "merked."
"He murked that quarterback! No mercy. He ain't getting up from that one."
"Did you see that fight? He murked that boy with one hit!"
"Don't even think of challenging him, man. He'll murk you before you can even reload. You got no chance."
A "Murky Sauna" is a drop shot. First warm 4 oz. of Guinness in either a pan or microwave. It shouldn't be boiled, just warmed. Then drop an half ounce of Bailey, and an ounce of vodka. For added murk use Pernod instead of Baileys.
Chad "Last night I got wasted on Murky sauna's, and when I puked it smelled like a fu*king gutter in Dublin"
Rupert "That sounds awesome......wait a murky what?"
Chad "You don't know what a murky sauna is.......really?!?