What does every combat mage need?

Depending on the Nation. Sometimes you have no items (Caelum for Example) except for a Runner with your Battlefield spell (Like Artifacts, ToS and SoS). Others, you usually just want to throw a Reinvigoration Item or Mobility Item (Boots of Messanger, Amulet of Resilence, Girdle of Might, Boots of Flying).

For Combat, combat mages. Like Dwarfs, Panii, Black Sorcerors, it's usually good to put something on them that will allow them to hammer deep into enemy territory (like Flying Boots) and a decent weapon (not always Wraith Swords).