Mark apparently forgot to mention this beforehand, prompting Wade to freak out.
Throughout the series there's a Running Gag of Wade (who has the most experience with 7DTD) giving Mark and Bob advice, which they either ignore completely or dismiss while mocking him note The whole "Mark Slow" thing happened because Mark didn't listen to Wade explaining how the skill system works.Mark lampshades his pronunciations of "room" and "tutorial" ("rum" and "terterial").Mark says that he'll pay them back by coming up with his own insults, but his struggle to do so gives Bob the chance to suggest "Wade Smart" and "Wade Handsome", which Mark finds personally offensive.
Bob: You know what, I'm Mark Slow and I've gotta go.