As a general rule, most magic items are considered to be quite unique. Even common magic items are, for the most part, common only in that they are available to all races – they are not so common as to be available to each and every character in your army. To represent this, only one of each magic item can be included in your army. In addition, a model can only purchase one magic item from each category.

There are, of course, exceptions to this rule of uniqueness. These are magic items carried by named characters and items considered to be 'extremely common'.