If I understand correctly, “all units must attack & defend together”
Not really. During Combat Move Phase …
@rulebook:
All combat movement is considered to take place at the
same time. …
Suppose that i will attack from my zone to the adjacent zone that contains no enemy units but enemy controlled.
But next zone has enemy units.1. At this situation my infantry unit attacks using 1 movement point to the empty enemy zone,occupied it and stops there.
2. My tank unit using 2 movement points, uses blitzing ability crossing the empty enemy zone,separated from infantry,
and finally attacks next zone that contains enemy units.
3- Remaining unit: 1 fighter unit; I don’t want to attack my fighter unit to the same enemy that my tank have attacked yet.
For example i want to attack another zone, another enemy unit.
You may move your units separately into different hostile territories.
So your tank may blitz as intended and your fighter can attack elsewhere.
But all those moves are “considered to take place at the same time”.
HTH :-)