@b0rk that one person who somehow manages to find every relevant StackOverflow question even though you searched it in 4 different ways and found nothing
Also: the infodumper who every 5 minutes goes off on a tangent to explain something you've been wondering about that none of the other experienced programmers/tutorial leaders thought was worth explaining (e.g. & in Rust, once I found an infodumper that shit slaps)