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Advanced Squad Leader Rulebook Updated and Erraticized

Navigation: Chapter D. Vehicles

D8 Immobilization & Bog

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8.1 IMMOBILIZATION: An immobilized vehicle cannot expend a Start MP, leave its current Location nor change its VCA, but may change its TCA if otherwise able to. Immobilization cannot be repaired during play. Immobilization usually occurs due to a variety of combat results [IFT vs unarmored (A7.308); CC (A11.5); DC (C7.7); minefields (B28.42); A-T mines (B28.52); Clearing mines (B28.71); ordnance fire (C7.3, C7.7); OVR (7.17)], but can also occur due to Bog Removal attempts (8.3), mechanical failure (2.51), or tracked vehicles attempting Excessive Speed (2.5). After all Passengers/Riders/SW/Guns have been unloaded/unhooked, an unarmed and unarmored immobilized vehicle is flipped over to its Wreck side (or removed if it has no wreck side).

       A2.51, D2.5, D8.1, D8.2, E3.65, & E3.724

       D6.5 & D8.1

8.11 MULTIPLE IMMOBILIZATION: The Inherent crew of an immobilized vehicle that receives another Immobilization result may be subject to an Immobilization TC (5.5).

8.2 BOG: Bog occurs only when a vehicle fails a Bog Check DR. A vehicle must make a Bog Check as dictated by the Terrain Chart for entering, or exiting or making any VCA change (one Bog DR per hexspine) in, certain terrain types termed Bog hexes. The Bog effect always takes place in the Bog hex, whether the vehicle is attempting to enter or (in the case of vehicles leaving a stream or trucks leaving a gully; B20.46) leave it. A bogged vehicle may not exit its current Location or change its VCA until freed, and therefore is Immobile, but may change its TCA if otherwise able to.

EX: A PzKpfw IIA exiting a stream across a non-stream hexside into a woods hex would possibly be subject to two Bog Checks. If it passes the first in the stream hex (0 DRM), it must take a second in the woods hex adding the +1 DRM for gaining elevation while entering woods and (unless making a Minimum Move) the +3 DRM for entry of woods at half MP allotment.

       B23.41 & D8.2

       D2.11 & D8.2

       D8.2 & D9.31

       A2.51, D2.5, D8.1, D8.2, E3.65, & E3.724

       B18.41 & D8.2

8.21 BOG CHECK: D8.21 Bog Check DRM If a Final Bog Check DR is ≥ 12, the vehicle bogs, is marked with a Bog counter, and must end its MPh immediately. The Original Bog Check DR is subject to the following cumulative DRM:




Vehicle has Normal Ground Pressure


Vehicle has High Ground Pressure


Vehicle is towing ordnance1 or trailer


Ground is specified as soft2, mud2, or snow-covered3


Ground is covered with Deep-Snow3/vehicle is crossing a Drift (E3.752)


Vehicle is not fully-tracked


Vehicle has Truck-type MP expenditure


Making an Abrupt Elevation Change


Exiting a Deep Stream & vehicle is neither amphibious nor water-proofed


Gaining elevation and entering woods


Moving into Wire


*Entry of woods, graveyard, wooden-building or rubble, at half MP allotment


*Entry of stone building at half MP allotment


Entry of Light Woods at one-third MP allotment

* +1 instead if moving from Factory hex to non-rubble hex within the same Factory (B23.742)

1 NA if ordnance is 76-107mm MTR

2 NA if on paved road or in building

3 NA if in building or on plowed road

       D2.11 & D8.21

       D8.21 & D8.23

8.22 BOG TC: The Inherent crew of a Bogged vehicle may be subject to an Immobilization TC when hit by sufficiently threatening ordnance (5.5).

8.23 MUD & DEEP SNOW: When scenario Weather (E3) is "Mud" or "Deep Snow", a vehicle [EXC: motorcycle (15.47); Aerosans (17.24)] must chance a Bog DR whenever it enters a hex or hexside without benefit of a paved/plowed road/runway hexside. The opponent makes one Secret (D.5) Bog Check DR for the vehicle's entire MPh (unless it enters—or, in the case of a stream, exits—a regular Bog hex in which case a Bog DR is also made for that hex; see also E3.752), plus a Secret dr. If the Secret Bog Check DR is sufficient to cause a Bog, note is taken of the Secret dr. The Bog takes place in a hex along the vehicle's path equal to the dr; e.g., if the dr was a 2, the opponent must declare the vehicle bogged in the second hex (/Bypassed hexside) moved into during that MPh which can cause such a Bog result MP expenditure is not a factor. If the vehicle does not move into that many hexes (/Bypassed hexsides) subject to Bog, no Bog result occurs.

       D8.21 & D8.23

8.3 BOG REMOVAL: D8.3 Bog Removal An otherwise-Mobile vehicle may attempt to eliminate its Bog status at the start of its MPh, provided it has not fired during its PFPh. Bog Removal is attempted by spending as its Start MP an amount of MP equal to an Original colored dr times a white dr (instead of the usual one MP for Starting). This MP cost is doubled if the vehicle is non-tracked. If the Final colored dr is 1-4, the vehicle is freed (even if its total MP allotment is < the modified start MP expenditure), but it is still in the Bog hex. The vehicle may then use any remaining MP to change-CA/move-normally. A -1 drm also applies to the colored dr if, in the same Location as the bogged/mired vehicle, there is a Mobile AFV (whose weight is ≥ 90% of the bogged/mired vehicle's weight) that has not Prep Fired, is CE, Stopped, and expends all its MP in Delay to assist in the other vehicle's unbogging attempt. However, if this other AFV assists thusly, both vehicles are then TI for the rest of that Player Turn, regardless of the Bog Removal DR's outcome. Both vehicles remain Stopped, and may not change CA, throughout their MPh—but may be Defensive First Fired on due to their MP expenditure. One armor leader in either AFV also modifies the colored dr.

Final colored dr



Freed at MP cost equal to white dr x colored dr (x 2 if not tracked)


Vehicle becomes Mired


Vehicle becomes Immobilized

       D2.5 & D8.3



8.31 MIRED: If a vehicle becomes Mired, its Bog counter is flipped over to the Mired side. Thereafter it receives a +1 drm to the colored dr of its future Bog Removal DR as long as it is Mired. The Mired drm is not cumulative for being Mired more than once.

8.32 TOW: A towed Gun may be unhooked from a bogged/immobilized/Abandoned vehicle with no special penalty for the vehicle's status.

8.4 TARGET STATUS: A vehicle bogged/immobilized during a MPh due to having entered-a-new-hex/used-VBM/been-in-Motion in that MPh is considered a moving target (C.8) for the rest of that MPh. However, a vehicle that begins its MPh bogged is considered a moving target only after it leaves its Bog hex/hexside, though the MP it expends in attempting Bog Removal will allow an enemy to Defensive First Fire upon it in its Bog hex with no Case J TH DRM.

8.5  Assuming an Inherent crew that is not broken/stunned/shocked, a bogged/immobilized vehicle may still expend MP for "non-movement" purposes (e.g., to change TCA, (un)load PRC, fire Smoke Dispensers, etc.), and its firing capabilities are unchanged except as related to its inability to change VCA. However, after the phase (A.15) in which it becomes thusly Immobile, its bow mounted weapon(s) may be used against a target in that vehicle's hex only during Defensive First Fire (thus its BMG is unusable in CC), only if the target is entering that hex from within the vehicle's VCA, and only a number of times ≤ the MF/MP expended by the target to enter the hex. See also C2.6.