We've all played pranks on friends. I would hope no one used terms like half n***er or anything of the sort. I would hope none of us threatened to crap in someone else's mouth or threatened to slap our friend's "real" mom.
Joke or not, it went too far, and they are not even buddies.
I guess I used to run with a pretty low class group. I had a couple of buddies, one hispanic (Puerto Rican) and one black in the military...the racial epitahs would fly fast and your mother jokes were a daily event. But, with that said, you'd have to be really close friends to do that. We'd always scale it back when in larger groups or people we weren't comfortable around.
they are not even buddies
I think this statement says it all.