These are the Mass Combat Made Easy rules written by Robin Stacey aka Greywulf, with some edits by Alex Schroeder.
Combat Scale is a multiplier that shows the size of the unit relative to the norm. It is only applied to damage in combat between units of different size. Hit Points, AC and all other stats remain the same. Each mass combat attack takes multiple rounds as units charge and clash into each other.
A unit of 20 goblin warriors will have CS ×5 as per the table below. The combat stats are still HD 1d8+1 (5 hp), AC 15, morningstar +2 (1d6) or javelin +3 (1d4). Against anything with the same Combat Scale (for example, a unit of 15 elves), an attack is resolved normally as if it was one goblin against one elf.
As more people join, it gets harder to find targets and to fight effectively. This is true for spellcasters, ranged attacks, and melee attacks. That’s why Combat Scale is not proportional to the number of combatants in a unit.
Combat Scale comes into play when battling against forces of a different size. It acts as a multiplier for damage dealt and it divides any damage taken, rounding down. Combat Scale is reduced as Hit Points as lost.
If the twenty goblins above are reduced to 2 hp, they have lost over half their unit, so are now CS ×4. When down to just 1 hp, they are CS ×3 with just 5 goblins remaining.
Cover (buildings, forest), feinting (to lure the enemy into a disadvantageous position), flanking (attacking from multiple sides), hiding (camouflage hours before combat) work as always. There is no moving silently and no hiding during a battle unless supported by magic.
|Fight downhill||Atk +1|
|Defending a trench||AC +4|
|Defending a wall||AC +8|
|Scaling a wall||AC -2|
|Fight in a marsh unless lizard||Atk -1|
|Fight in a river||Atk -4|
There are no attacks of opportunity.
Player characters and other heroes may join a unit. These heroes still roll their own attacks (and may use Power Attack) and deal damage (no Combat Scale applies). The unit may use the hero’s Initiative. If the unit takes damage, the hero can choose how much damage to take (no Combat Scale applies) before the rest is applied to the unit itself. If the unit is wiped out by the remaining damage (with Combat Scale applied), any extra damage has to be taken by the hero (no Combat Scale applies). Essentially the unit acts as a big meatshield.
The orc hero Severon joins the 5 remaining goblins in their fight against the 15 elves. The goblins hit for 4 ×3 points of damage, Severon deals 16 damage for a total of 28 points. The elves have CS ×5 and take only 5 points of damage, but since they only had 4 hp, they are wiped out.
Cleave allows an extra attack if at least one enemy was killed using a normal attack.
Greater Cleave allows an extra attack if at least one enemy was killed using Cleave.
Spell durations measured in rounds only work for a single round.
Spell durations measured in minutes work for 3 rounds.
Spell durations measured in tens of minutes or more work for the entire fight.
Damage dealing spells hit automatically, no save.
Other spells and special abilities are modified as follows:
|Spell or abilitiy||Note|
|Bard songs||Add typical level-based bonus to all combatants in the unit|
|Bless||Only works for units of 314 or less; effect lasts 3 rounds|
|Prayer||Only works for units of 200 or less; effect lasts 1 round|
|Flame Arrow||Use a spell per 50 archers|
|Entangle||Immobilizes a units of 50 or less for one exchange|