The goal here was to run these battles as close to AD&D rules as possible. I chose scaling of 1 to 20 since this gave me a manageable front line of 6 "squares" maximum for the units being fielded. I took the weapon percentages from the Orc Monster Manual entry to work out how many units with which weapons were available for them. The Irish armour and weapons were already specified. For the Kenku, although they carry staves and "samurai" swords, I saw they could get double damage with their 'body weapons' on a dive/charge (according to DMG p50) so I figured they would go with that.
|I did this in pencil at first until I was happy with the format|
Above is a cheat sheet with a section showing each group's chances to hit each other group, with weapon type vs AC applied. The Brovenloft Irish have an ability I call "Luck of the Irish" which allows them to cast the Chant spell by singing a battle hymn. I pre-applied the effect of this on their AC that so it wouldn't be forgotten and left a reminder to apply -1 to damage dice rolls.
Combat rounds run normally: sides declare actions, roll for initiative, and move, then attack if in range. For missile weapons I allowed "pass through" fire, which lets them shoot once at units moving through their field of fire, but before those units have engaged. This seems necessary in a mass battle since once melee units engage missile fire doesn't get much of a look in.
Each "square" of 20 engaged attackers rolls a d20, tallies the number of hits, rolls that many damage dice according to the weapon type of the attacking unit, then sums those rolls to get a total of damage to apply to the defending unit. Each side has an average hit point number for individuals, divide the total damage inflicted by the unit's average hit point number to find the number of "squares" killed, then assign any left over damage to "wounds".
Squares can be engaged with an overlap of 1, i.e. if a line of 4 squares is engaged with 3 squares of enemy, all 4 can roll. However if the unit had 5 or 6 squares in a line vs 3 squares in the opposing unit, these others would not be able to engage immediately. In a subsequent turn they could move to flank the 3 square unit and get a bonus of +2 to hit when they did so.
Normally, a unit can only move and engage in melee on the same round if they are charging. However, a square that is not engaged because of unit overlap can move to engage a square in the overlapped unit, but in this case cannot charge when doing so.
At the end of each round check Morale as per normal rules based on the loss of squares.
This leaves PCs and what they can do:
- I allow the party to order the units around, choose their formation and tactics etc, with the assumption that the orders will be carried out if possible.
- PCs embedded in a unit make attacks as usual, their combined damage for the round is divided by 20, and the result added to the running total of "wounds" to the opposing unit. If this is enough to increase the wound total to the unit's average hit points, then remove a square from it.
- Cleric healing can be applied to individuals as normal, but it can also be applied to the group. Tally the total number of hit points healed and divide by 20, subtract this from friendly unit "wounds". This might be enough to save a friendly unit for one more round.
- Damage spells would have worked the same as other damage, with the inches of area of effect counting for one "square" of a unit (since that is the scale). This didn't come up in practice during the session.
- When a square is removed from a unit, roll to see which square it is and check if that square contains any PCs. If PCs have not nominated which square to fight in then determine this randomly. If a PC is in a square that is killed, he automatically takes damage equivalent to the unit HP (rounded down) and can then move to join the next square if he is still alive.