When an obstacle is on a Terrain hex, the Battle dice reductions of the two are not cumulative. The best protection is the only one that matters. For example, a bunker on a hill reduces the number of dice rolled by a tank attacking from a lower elevation by 2, not 2+1 (bunker protection is 2, hill is 1).
Example: a sandbag on a village does not add anything to the village protection (village defense is 2/1, sandbag defense is 1), though it does provide an additional feature: any unit in the village may ignore the first flag rolled against it, due to the sandbags.
Bunkers
Movement: An Infantry unit may battle the turn it moves onto a Bunker hex. An Armor or Artillery unit may not move onto a Bunker hex. Artillery units that start on a Bunker hex may not move from the hex.
Battle: Only the side noted in the briefing notes may claim a Bunker as a defensive position.
When battling an enemy unit that is on a Bunker hex, Infantry reduce the number of Battle dice rolled by 1, Armor reduce the number of Battle dice rolled by 2 and Artillery Battle dice are not reduced.
Remove one Artillery figure for each retreat Flag rolled against an artillery unit in a bunker.
A unit in a bunker may ignore the first flag rolled against it.
Line of Sight: A Bunker blocks line of sight.
Hedgehogs
Hedgehogs were obstacles against tanks and landing craft. They were usually made of steel rails assembled together. They could also be made of wood, with an anti-tank mine at their top. Unexpectedly, the Allied infantry troops used them for cover while moving on beaches.
Movement: Only Infantry units may enter a Hedgehog hex. No movement restrictions.
Battle: No combat restrictions. A unit on a Hedgehog hex may ignore the first Flag rolled against it.
Line of Sight: A Hedgehog does not block line of sight.
Sandbags
Movement: No movement restrictions. When a unit leaves a hex with Sandbags, the Sandbags are removed.
Battle: A unit in a hex with Sandbags is protected on all sides, not just along the hex-sides where the Sandbags are placed. When a unit does not benefit from any protection for its terrain, the sandbags reduce the number of Battle dice rolled by 1 when attacked by Infantry or Armor. As usual, Artillery Battle dice are not reduced.
A unit hidden behind sandbags may ignore the first flag rolled against it.
Line of Sight: A Sandbagged hex does not block line of sight.
Wire
Movement: A unit that enters a hex with Wire must stop and may move no further on that turn.
Battle: An Infantry unit that is on a hex with Wire, will reduce the number of Battle dice it rolls by 1.
An Infantry unit that is eligible to battle may remove the Wire instead of battling. Armor must remove the Wire and may still battle.
Line of Sight: Wire does not block line of sight.
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