A Mixed Unit most often consist of two different Troop Types, with one or more handlers that drive the rest of the unit forward. The handler(s) must be deployed in the rear rank(s) of the unit, as centrally as possible. Mixed Units cannot be joined by characters, unless specified.
If a Mixed unit is required to take a characteristic test, this is done using the characteristics of the unit itself, not the handlers. The only exception is LD tests, which are taken using the unit’s highest LD value. When the models in a unit with Mixed Unit have different M allowances, the handlers M value is ignored, unless they are the only models remaining. Any special rules that the unit might have do not apply to the Handlers unless specified. Note that if the unit has Expendable, Swiftstride or Vanguard, this also applies to the Handlers.
As long as the unit (but not the handlers) have a unit strength of 5 or more, any missile hits are resolved against the unit itself. At less than unit strength 5, the controlling player decides who is hit, but must allocate one hit on each model before they can add a second hit on a model; they must allocate two hits on each model before they can allocate a third, and so on. Hits from templates are resolved against the handlers as normal. In close combat, the handlers can only be attacked by models who are in base contact with them.