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Bumhug
/chunklimits: Shows a list of blocks you can only place a limited number in a chunk
/gamma: Toggle your night vision
/nbtshow: Show NBT data for the item in your hand
/pdcshow: Show PersistentDataContainer data for the item in your hand
/ping: Shows what your ping to the server is.
/reloadinventory: Reload a player's inventory from before the last time they died
/rules: See the Rules of Civ+.
/setrepaircost: Set the repair cost of the held item