Once all five nations have locked their orders, the turn proceeds to the Movement/Combat phase. During this phase, units attempt to move according to the orders they were given. This will likely result in conflicts as opposing units attempt to occupy the same territories. Whereever conflict occurs, unit movements are stopped, and a battle ensues to determine which units remain to take control of the disputed territory.
The movements of units is fully automated. It proceeds according to the orders given by each nation. Not all orders given will be fulfilled, because conflicts in the movements of opposing units cause them to stop, nullifying all remaining orders for those units. The rules controlling movement conflicts are grouped according to the medium in which each unit moves.
Sea units can only move through sea zones. Sea unit conflicts which stop movement can only occur with other sea units. Sea unit movement is not stopped by passing air units; however, if a sea unit's last position is the same as an enemy air unit's last position, there is a conflict in that sea zone. Submarines can move in a stealth mode: in this mode, they will not conflict with enemy units, even if they both occupy the same zone. Nonetheless, if a submarine's last position is the same as an enemy sea or air unit's last position, there is a conflict, regardless of the use of stealth.
There is a kind of movement conflict which is more complicated than the above described model. It happens when a collection of units are ordered to move from a source zone to a destination zone and a collection of enemy units has the exact opposite source and destination. In other words, a group of units is ordered to move from zone "A" to zone "B", and an enemy group of units is ordered from zone "B" to zone "A". The zone in which the conflict will occur must be determined. To do this, the sum total economic value of the two forces is computed, and the force with the greater value advances while the force with the lesser value does not. For the purpose of this economic computation, the value of any friendly air units accompanying the group of sea units (where the source/destination of the sea units is the same as the final source/destination of the air units) is included in the computation. This is despite the fact that air units alone would not cause such a movement conflict.
Land units can only move through land territories. Analogous with sea units, their movement can only be stopped by other land units. Land units can be carried across sea zones on transport units, but the movement of the land units themselves is strictly on land territories. Land units carried on transports can not move before or after the transport process.
Air units can fly over land and sea. Their movement doesn't conflict with opposing units, except for the final territory in the air unit's order. If an air unit passes over an enemy territory which includes an AAgun during its "flight", that AAgun will shoot at and possibly destroy the air unit. This is calculated separately from the land and sea battles among units. Air units can't be ordered to use their entire movement allotment. Some of their potential movement must be kept in reserve in case the air unit encounters combat and must vacate the territory of its final ordered destination. The amount that must be reserved must be adequate for the air unit to move to a safe territory after combat. The determination of which territories are safe is done during the Orders phase; it is possible that a territory that is safe during Orders is not safe after the Combat phase. The air unit can complete its entire movement allotment in the Post-combat phase.
When the last nation locks orders, the movements for the turn are automatically computed. First, shots against any air units that are ordered to move over any AAguns is computed. Next, the movements are computed, detecting conflicts and stopping orders when necessary. Next, all industrial raids are resolved. Finally, the first shots of each battle for the turn is computed. In order to accomodate the possibility of having a sea battle followed by an amphibious assault, all sea movements and battles are resolved first, then all land movements and battles (including the unloading of transported land units and amphibious assaults). Air unit orders are classed as sea or land movements according to the final destination of the order.
All the battles detected can be played and resolved simultaneously. Since all the sea battles are resolved before any land battles, there is no chance of any battle interfering with any other. The battles are interactive, as the players must choose which units get destroyed in each round and whether/when to retreat units.
Any unit which moved to reach a battle shoots with its "attack" strength value. Any unit which didn't move yet finds itself in battle shoots with its "defend" strength value.
Some retreat is allowed (described below). Retreat for land units and retreat for non-submarine sea units is not, because it is possible for units on opposite teams to want to retreat to the same territory.
resolving hits from battleship bombardment, if an amphibious assault is involved in a land battle and a battleship was ordered to bombard the coastal/island territory. This can only happen once per amphibious assault, and the destroyed units never shoot back.
resolving hits from submarine shots: if submarines are present, they shoot before any other sea units or air units. Any units destroyed by a submarine don't shoot back (except other submarines, since all submarines shoot simultaneously).
resolving all other hits: all other units shoot after bombardment or submarines have shot.
retreat: surviving air units which moved into conflict may retreat after all units have shot and all destroyed units are choosen for that round. In addition, any submarines may retreat if the only enemy units remaining in the battle are air units.