Designing Bogey Encounters
Generally speaking, vehicle combat encounters are set up the same way that traditional melee encounters are set up. For example, an even-CR vehicle combat encounter consists of one bogey (NPC-operated enemy vehicle) per PC-operated vehicle of the same CR as the average character level of the party. Bogeys can even have roles, exactly like monsters, with many of the same benefits those roles provide (see Bogey Roles for details).
However, a few of the rules that apply to PC-operated vehicles are different when applied to bogeys. This page addresses these differences and makes some recommendations for designing interesting vehicle combat encounters.
NPC Vehicles are referred to as "Bogeys" to differentiate them from monsters and from PC-operated vehicles.
Bogeys can make facing changes after move actions slightly more efficiently than PC-operated vehicles. After any Move or Double-Move action, a Bogey can choose to make a single 45-degree facing change or a 90-degree facing change, either left or right of their current facing, without the need to expend focus. If they wish to change their facing more than this, they must spend their focus for the round to do so (see below).
Bogeys do not accumulate focus, nor can they accumulate stress. Instead, bogeys can perform the Focus Action swift action to then perform any one action which requires focus. This is intended to keep the GM's attention on the combat, instead of on book-keeping. Note that the Focus Action swift action doesn't actually do anything, except allow the bogey to then perform an action which requires focus.
If a bogey is forced to spend focus, but has no more swift actions available this round (e.g. due to moving off the edge of the map), they take 1 point of damage per point of focus they are forced to spend. This damage cannot be mitigated by any defenses (such as DR) and is always deducted from the bogey's remaining durability. If a minion-role bogey takes damage from pilot error (needing a focus action they don't have), they are instantly destroyed, and award XP and salvage as though the players had defeated them (which is usually true, since the players probably forced the error in some way).
The most common reasons that bogeys will need to spend focus are:
- Facing changes greater than 90-degrees after a Move or Second Move action
- Performing the Sudden Halt action in place of a move
- Making an attack outside of their forward firing arc
Set Up The Encounter
The GM should describe or set up the encounter. This must include stating where, on the map, the PC's can set up their ships' starting position and facing, as well as setting up the NPC ships' starting location and facing.
It is very important that each participant in the encounter set their facing before the combat begins, as this determines the direction of their first move action.
The GM should also place any blocked, impeded or difficult terrain that is present in the encounter. Some encounters may not have any terrain, but adding at least a little terrain is nearly always a good idea. In most cases, difficult, blocked and impeded terrain will follow the same rules as those of traditional melee combat, but the GM should also decide if there are any unusual rules in play for the encounter. For example, a particularly large area of blocked terrain in an Aethereal combat might have a gravitational pull, pulling all ships 2 spaces closer to it at the top of each round's initiative order. Alternatively, a chariot-based fight on a frozen lake might have special rules for skidding further than intended any time a chariot tries to turn.
Most terrain should also be destroyable in a vehicle combat encounter. GM's should decide what Maneuver Defense and how much durability each square of terrain has, and what happens to the square after it is reduced to 0 durability (e.g. it might change from blocked to impeded, impeded to difficult, and difficult to normal).
Finally, the GM should designate any squares on the edges of the map which count as 'escape squares' for the NPC's, and any squares which count as 'escape squares' for the PC's. These can be the same squares, or different for each faction in the encounter. Any ship wishing to flee the encounter must move through one of these squares before leaving the map. Escape squares should generally be far enough away from starting positions that an actual combat encounter can occur before any ships reach their escape point.
GM's are reminded that if NPC ships want to run, and they're already so close to the exit that no one can stop them, then you're not really in a combat encounter yet, and there's no reason to play things out in initiative order. Wait to run this encounter until the PC's have boxed the fleeing NPC's into a cove, or chased them near a reef, where they can't easily slip past. Another way to avoid doing this is to always treat ships which flee an encounter as defeated for experience purposes (though obviously not for treasure). Don't give your PC's free XP; make them work for it.