User blog comment:Sannse/Five Things Every Admin Should Know/@comment-33143709-20150709235136/@comment-8-20150710171102

I'm sure you are right that there are at least 20 things, 452. Mostly the ones I chose are about understanding what's going on on the wikia.

Others people have mentioned are more about managing the daily flow of edits (protection, rollback, blocking...)

Then there are the less immediate tasks often found in Special:SpecialPages (fixing redirects, adding categories...)

There are probably other groupings too, but understanding what's going on goes top of my list :)