Minecraft Minions are created by doing Evil and Using the Master's Staff.You can have up to 4 minions at once, but you can change that number in the files.They can help with digging and they carry a pickaxe all the time unless they are carrying something you told them to.
You can command them to Carry you by right clicking on the block below you,Carry an animal by right clicking the block beneath the animal,Move somewhere by right clicking the block you want to go to,Follow you by right clicking and holding briefly,Get ore by right clicking the ore,Put what they are carrying in a chest by right clicking a chest (from a distance so you don't open it)Dropping what they have by right clicking them.
Press 'G' to open the menu with the advanced commandments in.
Dig Mineshaft.They dig mineshafts 5x5 and put stairs in.
Strip Mine.You can pick where they do it and they pick up ores on the way.