/cast [target=Party1, exists, dead] Ancestral Spirit
/cast [target=Party2, exists, dead] Ancestral Spirit
/cast [target=Party3, exists, dead] Ancestral Spirit
/cast [target=Party4, exists, dead] Ancestral Spirit
/cast [target=Party5, exists, dead] Ancestral Spirit

Figured I'd do something like this for everybody, each character in different orders. So they'll almost always rez different targets via one button.