Multiproduce is a method of letting multiple units be produced with one produce command (at one cost for all the units). Multiproduce is only available in GAE 0.4.x plus. If a production command is told to multiproduce, it can only produce that number, never less. So if multiproducing 3 swordman, they have to be done in groups of 3, and you can't produce just one unless a separate command is made for that.