/jobs list ---> lists the jobs and lets you pick your professions. You need some jobs to make money, which you can use to trade with players, make shops, and purchase stuff from /spawn. I recommend Miner and Builder for everyone, and you get 6 jobs in total.
/mcstats -----> see your McMMO stats
/mctop ------> see the McMMO leaderboard
/mcrank ----> see your rankings for all skills
/sethome ---> sets a home point, you can have a few of these
/delhome ----> deletes a home point
/back ---> returns you to the last place you were
/ms help -----> guide to using the magic spells plugin
/spawn ------> takes you back to Spawn City Overworld, the city offers tons of stuff: an enchanting table, curiosities to explore (double-glitched jungle temple, an empty dungeon that myself and another admin built [real version is in the Adventure world]) shops selling monster spawn eggs, Ender chests, and NPC eggs so you can start or improve an NPC village if you'd like. Also portals to all of the worlds; Adventure, Creative, War, Cityworld, etc.
-cauldrons are infinite water sources.
-to lock a chest, place a sign on the front of the chest. You can use /lockette to edit the sign and allow multiple users to access the chest.
I'm sure there's more stuff but I can't think of it at the moment. Anyway hope to see some more people online!