Arthur

a.8ball › Ask the magical eight ball a question.
a.cat › Get a cat picture.
a.dog › Get a free dog photo.
a.math › Evaluate math expressions and conversions.
a.mchistory › View all the previous names of a Minecraft user.
a.mcserver › Get information about a Minecraft server
a.mcskin › Get the skin of a Minecraft player
a.strawpoll › Create a strawpoll.
a.ud › Define a word or phrase using the glorious urban dictionary
a.xkcd › Get a random, chosen, or latest xkcd comic.

a.webshot › Take a picture of a website.
a.endpoll › End a currently started poll early
a.poll › Start a poll
a.help › View the help menu.
a.info › View information about Arthur.
a.invite › Invite Arthur to your server.
a.mp3 › Get an mp3 file of a YouTube video or Soundcloud song
a.suggest › Suggest a command or feature to be added to Arthur.

a.dice › Rolls a dice
a.hug › Hug Arthur (or someone else)
a.l › L
a.lenny › ( ͡° ͜ʖ ͡°)
a.meme › Get a random meme.
a.owoify › Owoify some text
a.reverse › Reverse some text
a.spacify › A d d s o m e s p a c e
a.spongebob › It'S tImE tO sPoNgEbOb SoMe TeXt
a.stopwatch › Time something with your dandy stopwatch

a.humongoji › Enable or disable humongojis in a server. They're wumbojis, but better.
a.levels › Enable or disable leveling for a server.
a.blacklist › Blacklist a user or role from using Arthur in your server.
a.levelmessages › Toggle level up messages for your server.
a.prefix › Set or view the server's prefix.
a.unblacklist › Unblacklist someone previously blacklisted from Arthur.

a.guildlanguage › Set the language of Arthur for your server. User settings overwrite.
a.langinfo › Get detailed information about a language.
a.language › Change the language of Arthur for yourself. Overrides server language.
a.languages › List all languages that Arthur has available.

a.leaderboard › Show the leaderboard for the current server or global.
a.xp › Show your current XP and level
a.xpinfo › Gives information about Arthur's leveling system.

a.forceskip › Force skip the current song
a.like › Like the currently playing song
a.liked › View all your liked songs
a.likedlb › Get a list of the top liked songs.
a.loop › Loops the current queue of music indefinitely.
a.move › Moves a song at position a to position b.
a.nowplaying › See what song is currently playing
a.npnotify › Send a message when a new song starts
a.pause › Pause the currently playing song
a.play › Play a song or add it to the queue
a.playnext › Queue a song next in queue
a.queue › View the current queue
a.remove › Remove a song from the queue
a.resume › Resume the currently playing song
a.shuffle › Shuffle the current music queue
a.skip › Skip the current song.
a.stop › Stop all music and leave the channel.
a.unlike › Unlike that one song you liked

a.airhorn › Alias for play file airhorn
a.airhorns › Alias for play file airhorns
a.badumtss › Alias for play file badumtss
a.interiorcrocodilealligator › Alias for play file interiorcrocodilealligator
a.oof › Alias for play file oof
a.oofcat › Alias for play file oofcat
a.rickroll › Alias for play file rickroll
a.sadoof › Alias for play file sadoof
a.sadviolin › Alias for play file sadviolin
a.traphousebob › Alias for play file traphousebob