Special Battles and Movement

Vehicles are everywhere in Starfinder, from sleek enercycles to bulky hovercabs, and while mounted travel is considered by some to be an antiquated mode of travel, mounted combat is far from a lost art.

The logistics of vehicular combat and mounted combat take some extra work. Ensure the fight takes place in a location with plenty of space to move since you'll likely be dealing with multiple larger creatures or vehicles. For a fight in which only one side has vehicles or mounts, you might want to use an environment with a few areas too small for vehicles and mounts, so the side on foot can get a tactical advantage there to offset the other side's greater mobility.

When the PCs are mounted, their enemies should focus most of their attacks on the PCs, not their mounts. When PCs fight mounted enemies, try to keep the mount's level fairly close to the PCs' level; rather than putting an 11th-level enemy on a 2nd-level shotalashu, use a 9th-level surnoch, an 8th-level arabuk, or something similar. This will fit better thematically and prevent the enemy from being dismounted too easily. If a mount is knocked out, the rider might be able to dismount without trouble if the mount was stationary, but if they were in motion, you should probably have the rider attempt a Reflex save. If they fail, the rider is thrown a short distance and falls prone. Setting a simple expert DC of 20 often works well for such checks.

When the PCs are driving vehicles, their enemies should focus most of their attacks on the PCs, not their vehicles. Alternatively, if the PCs have greater or total cover while within their vehicle, their enemies should focus on either forcing or drawing the PCs out of their vehicle or on boarding the vehicle. When the PCs fight enemies in vehicles, try to keep the vehicle's level fairly close to the PCs' level. Consider the transport method of selected vehicles. Enemies driving wheeled vehicles are easier to stop or hinder than enemies driving hover vehicles, and the tactics PCs can employ against such enemies should likewise differ.

Vehicular and mounted combat on a grid is difficult for a running fight with both sides racing at full speed. In these situations, it's better to forgo the grid, though miniatures can still help for relative positioning and distances for ranged attacks. For such a race, consider using the chase subsystem instead.

The mount rules are for common cases: intelligent creatures riding animals. However, you might allow someone to ride a beast, robot, or other type of creature by making a few adjustments. For an intelligent mount (such as a skreesire), use the standard rules for mounted combat, but instead of attempting a check to Command an Animal, the rider uses the same number of actions to ask the creature to do what they want. As the GM, you determine whether the creature does as requested and whether Diplomacy checks or the like are needed. For a technological mount, instead replace the check to Command an Animal with a Computers check. If one of your PCs is Tiny, they might want to ride on another PC's shoulder. In this case, the two PCs should both roll initiative and act together on the lower count, and they gain only two actions at the start of their turns instead of three since the larger PC must spend one action keeping the smaller PC balanced, and the smaller PC must spend one action holding on.

Flight is common in Starfinder, whether via natural ability, magical enhancement, or technological assistance. Both PCs and enemies will gain access to flight early, so being able to participate in aerial encounters is important. For PCs who choose not to invest in a method of flight, ranged weapons and spells are very useful tools, as are other environmental features, such as trees, balconies, catwalks, machinery, and rooftops.

Determining positioning in the air can be tricky, and it's best to be more relaxed with movement rules, flanking, and so forth than you would be on a flat grid. Note that battles can get more spread out with flight. If any creature is flying, it's important to establish the height of potential obstacles in the area early. This way, no one is surprised to suddenly find out the ceiling is lower than they thought or tall trees create a barrier.

The rules for flight say that a creature might need to attempt an Acrobatics check to Maneuver in Flight to pull off tricky motions. You can generally use the same judgment you would while calling for Acrobatics checks when someone is moving on the ground. Trying to dive through a narrow space or make a sharp turn might require checks, usually with a simple DC.

Falls can be deadly and often happen when fly or a similar spell gets dispelled. This is part of the risk of flying! Flying enemies might keep closer to the ground to avoid this danger, or they might use magic or equipment to prevent or reduce the damage.

Aquatic combat poses two primary challenges for non-aquatic characters, which are both easily overcome at low levels: breathing underwater and lacking a swim Speed. All armor has basic environmental protections that enable a user to breathe underwater or in a vacuum. Lacking a swim Speed is likewise simple to deal with, except for characters with poor Athletics, who might need to strategize around their shortcomings. The DC to Swim underwater shouldn't be very high—typically 15, or 13 in calm water.

Like aerial combat, determining positioning underwater can be tricky, and it's best to be relaxed with movement rules, flanking, and so forth when running aquatic combat. When someone gets knocked out underwater, they usually float up or sink down. You decide based on their buoyancy; most adventurers carry a heavy enough load to sink.

When one group is in the water and another is outside it, note that the aquatic combat rules for attacks apply when either party is in water. You might decide that a character in the water is concealed against someone outside it due to distortion, and vice versa. All nonhazardous liquids use the same rules as water.

Fighting in a vacuum is perhaps the most challenging environment for PCs to contend with. While breathing in a vacuum is a simple matter thanks to the basic environmental protections granted by armor, movement in zero gravity is tricky. This doesn't mean fighting in a vacuum is a highlevel threat! On the contrary, zero-gravity environments are commonly encountered all throughout a character's adventuring career.

To run efficient encounters in a vacuum, ensure you and your players know how the untethered condition and Push Off action function. Many characters will develop strategies to mitigate the untethered condition or its penalties, whether through ancestry feats, magic spells like personal gravity, or technological items like magboots. Even simple cables used as a tether can be useful tools to PCs fighting in a vacuum!

Ensure the environments you describe have plenty of material around for PCs to Push Off of, cling to, use as cover, and fling at their attackers. Remember that the threat of being pushed out a starship's airlock or falling off a ruined structure floating in the Drift can bring an effective narrative tension to an encounter, even if the PCs manage to avoid being tossed into the vacuum!