It's amazing how simple it gets to write/edit these rules when I only have to reference the suppression rules section instead of writing bits of them all over the place. :)
Here's the 1 page of rules for the Reaction Phase.
The Reaction Phase
Once the current player has performed an action with each of their units, their opponent will get a chance to react to those actions before the close-combat phase begins.
Action Phase Sequence
- Roll For Suppression
- Perform Defensive Fire
- Rolling For Suppression
This is quite important, as suppressed units may not perform defensive fire. Nor, during their own turn, may they hold objectives, or do anything but fall back during their action phase.
At the beginning of the reaction phase, each suppressed unit in the opposing player's strike force will roll a standard leadership test. If the test is passed, that's unit's hit-die (and one nerve marker) will be removed. Causing the unit to no longer be considered to be suppressed.
If a suppressed unit fails its leadership test, it will remain suppressed.
(Edit: Moved the Officer rule here from the action phase.)
Officers aren't just there to look cool. They're also expected to... gulp... lead the troops! Especially when they are a bit shaky, but must still hold the line. This is done by issuing Orders.
During the reaction phase, all units that are within 6" of a friendly officer may use that officer's current leadership (Ld) instead of their own when rolling for suppression.
The Defender's units aren't going to just stand there and let an attacking unit charge into close-combat with them. If they can, they'll attempt to shoot an attacking unit as it runs towards them!
Any unsuppressed unit in the opposing player's strike force may, during the reaction phase, perform defensive fire against any of the current player's units that are within 6" of their position.
Other units in the opposing player's strike force aren't just going to stand still either. If they can, they'll try and help their brothers in arms by firing at an attacking unit.
Opposing units outside of the Close-Combat, which are not suppressed, will also have the opportunity to conduct defensive fire. But they may only do so if the distance from their unit leader to the attacking unit is within that unit's current Awareness Range (Aw).
Note that any unit which performed an At the Double action in their last Action Phase may not perform Defensive Fire.
Performing Defensive Fire
Units performing defensive fire don't have a lot of time to react before the foe will be into them.
All defensive fire from a unit will follow the Snap-Fire rules. No model in a unit which is performing defensive fire may fire at more than one target unit.