
Jolly: They ain’t paying us enough for this, man.
Kip: I’m afraid I have some bad news.
Box: Well, that’s certainly a switch.
In ARC – The Underworld, the combat action between the ARC and REZ characters takes place in three forms: ranged, explosive ranged, and close combat. All three rely on a similar resolution method using a polyhedral dice comparison system. With this mechanic, both the attacking and defending players work together to determine the results. One force is not required to wait while the other plays through its turn. This way, a force is always in control of its fate.
The game includes a set of d12 (black), d10 (blue), d8 (green), d6 (white), and d4 (red) polyhedral dice for both sides. In most cases, rolling one or two dice is used to resolve combat. The play of Action cards may add a third die to the mix.
Characters activate one at a time during a turn, making a single optional attack. Once a combat is declared, the attacker announces the dice to roll based on the weapon employed, and if playing an optional Combat or Move Action card. The attacker may play one or the other, not both. The defender(s) then determine the dice to roll based on their built-in defense and any cover offered by the square occupied, and if playing an optional Defense Action card. Unlike attackers, the same character may play a Defense Action card each time it’s attacked during a turn.
Note that explosive ranged weapons can impact multiple characters with a single attack if they occupy the area covered by the weapon. For example, grenades, both ARC and REZ, affect the target square and the eight surrounding squares, for a total of nine squares.
In all combats, only the highest roll on a single die counts towards both the attack result (AR) and the defense result (DR). When rolling multiple dice, the results are never added together. By applying plus or minus combat modifiers, such as character actions like moving while attacking or using Action cards, the final result can increase to any value but will never be reduced below one.
In all cases, the magnitude of the AR result compared to the DR result determines the number of hits applied, if any. The AR must be greater than the DR for any hits to occur. The number of hits from a single combat can also cause a defending character to become Suppressed or Stunned.
Example

REZ Guard 5 is employing ranged combat to shoot at Grip with its equipped Beamer. A Beamer has two modes of fire to choose from: Semi rolling a d10 and a d4 or Burst rolling a d12 and a d4. The number of small red dots depicted under the dice sets indicates the mode of fire: one for Semi, two for Burst, and three for Auto (not available to a Beamer).
Because d12d4 is clearly better than d10d4, why not always fire a burst? There’s always a trade-off. The value shown in the gray box within each set of dice indicates the AR result that causes the Beamer to become unloaded. It has a 30% chance to unload when firing in semi mode (3/10) and a 42% chance in burst mode (5/12).
When determining an unload check for ranged combat with multiple dice rolled, the unload check only considers the weapon’s unmodified result from the primary die, which is the strongest. With the Beamer, that’s the d10 in Semi mode or the d12 in Burst mode. Why is it compared against the unmodified result? This ensures it remains a constant, unaffected by any modifiers that might increase or decrease the unload chance. If less than the listed value, the weapon is now unloaded.

Because all ranged weapons have a limited number of reloads—4 for the Beamer, as shown by the value at the bottom of the counter next to the two bullet icons—players must weigh the chance of a higher AR result against the increased risk of the weapon running out of ammunition.
Grip is located in terrain that provides a d6 cover located within normal range for the Beamer. The REZ player announces Burst mode and states no Combat or Move Action will be played. Grip’s in-built defense is a d8 (upper left of his character card) plus the d6 for the square’s cover for a combined defense of d8d6.
In playing the game, it will quickly become apparent that cover is always your friend. Standing out in the open is typically a terrible idea.
Both players simultaneously roll their dice. The REZ rolls are d12-3 and a d4-4, for an AR result of 4 (never discount the d4s as they may carry the day). Definitely hoped for better.
The ARC rolls are d8-2 and d6-3 for a DR result of 3. Very disappointing, but thank goodness for the cover. With the AR>DR, Grip must apply one hit. The Beamer is now unloaded, since 4<5.
