In Cali at least it means to do something with around a dozen other people with an assertive mindset. Often in regards to going to a party or club with liquor and drugs involved. Not necessarily with hostile intentions.
When you’re a living vampire named Michael Morbius and confront a bunch of bad guys in a spooky place, you then shout “It’s Morbin Time!” at the top of your lungs and then proceed to morb over everybody until there’s not a living thing left to morb.
I knew I was fucked when I heard a loud noise with the phrase “It’s Morbin Time!” being yelled as I start getting morbed on