I have 2 macros:

1, all mages sheep their focus.
/cast [target=focus] Polymorph


2. all mages sheep ANYTHING THEY CAN FIND. WOOOOOOOOO

Mage a:
/targetenemy
/cast polymorph
Mage b:
/targetenemy
/targetenemy
/cast polymorph
Mage c:
/targetenemy
/targetenemy
/targetenemy
/cast polymorph
Mage d:
/targetenemy
/targetenemy
/targetenemy
/targetenemy
/cast polymorph