You must have Convention, Strunk and White, Civic Duty, and Deputy to stand for election as a moderator. (I'm not actually sure whether that's SE-wide, or just SO.) And at one point you had to have Strunk and White to qualify for Reviewer. I don't know if that's still the case or not because I have it.
For these four, and perhaps for others if they exist, can we add to the badge descriptions page?
10 posts with score of 2 on meta. You must hold this badge to be nominated as a moderator
Edited 80 posts. You must hold this badge to be nominated as a moderator
... etc ...
Completed at least 250 review tasks. This badge is awarded once per review type and only to those with the Strunk and White badge
Something like that...