MSRD:Mecha Movement and Combat

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This material is published under the OGL 1.0a.


Combat between mecha is conducted much as it is between characters. Characters operating mecha are simply much larger and stronger than they would otherwise be, and they can wield truly frightening weapons. However, they still obey the essential rules of movement and combat. They still threaten squares within their reach, take move actions and attack actions, duck behind cover to gain a bonus to Defense, and so forth. In some respects, however, mecha movement and combat differs from character movement and combat. The following sections describe specific situations that arise when mecha maneuver and clash on the battlefield.


It takes a full-round action to climb into a mecha’s cockpit and a move action to activate its various systems so it can move and fight. It takes a full-round action to get out of a mecha unless an HV-5 Haven escape pod or similarly expeditious device is used (see Miscellaneous Equipment).


Mecha operators use the Drive skill to operate their mecha on the ground and the Pilot skill to operate their mecha in the air or in space.

In general, mecha operators don’t need to make Drive or Pilot checks to steer their mecha around the battlefield. However, these skills may come into play in combat under the following circumstances:

  • When trying to move past a foe without provoking an attack of opportunity, a mecha operator can make a Drive check or Pilot check (as appropriate) instead of a Tumble check.
  • A mecha operator can oppose a trip attempt with a Drive check (if on the ground) or a Pilot check (if in the air).
  • A successful Pilot check can pull a mecha out of a stall (see Flying Mecha, below).
  • A character in a copilot cockpit can use the aid another action, making Drive or Pilot checks (as appropriate) to aid the Drive and Pilot checks of the mecha’s operator.


The vehicle rules are entirely appropriate for ground cars and other normal modes of transportation; however, even a clumsy mecha is more maneuverable than a normal vehicle.

On the ground, mecha move as characters. They can turn at any time, move in any direction, and stop on a dime. In the air, though, they are more limited.

Most flying mecha have to s low down to make a turn, and many are limited to fairly wide turns and must maintain a minimum forward speed. Each flying mecha has a maneuverability rating, as shown on Table: Flight Maneuverability. A mecha’s flight systems determine its maneuverability.

Minimum Forward Speed: If a flying mecha fails to maintain its minimum forward speed, it must land at the end of its movement. If it is too high above the ground to land, it falls straight down, descending 150 feet in the first round of falling. If this distance brings it to the ground, it takes falling damage. If the fall doesn’t bring the mecha to the ground, the operator must succeed at a Pilot check (DC 20) to recover. Otherwise, it falls another 300 feet. If it hits the ground, it takes falling damage. Otherwise, it has another chance to recover on its next turn.

Hover: The ability to stay in one place while airborne.

Fly Backward: The ability to fly backward.

Reverse: A mecha with good maneuverability uses up 5 feet of its speed to start flying backward.

Turn: How much the flying mecha can turn after covering the stated distance.

Turn in Place: A mecha with good or average maneuverability can “spend” some of its speed to turn in place.

Maximum Turn: How much the mecha can turn in any one space.

Up Angle: The angle at which the mecha can ascend.

Up Speed: How fast the mecha can ascend.

Down Angle: The angle at which the mecha can descend.

Down Speed: A flying mecha can descend at twice its normal flying speed.

Between Down and Up: An average, poor, or clumsy mecha must fly level for a minimum distance after descending and before ascending. Any flying mecha can begin descending after an ascent without an intervening distance.

Table: Flight Maneuverability
Maneuver Perfect Good Average Poor Clumsy
Minimum forward speed None None Half Half Half
Hover Yes Yes No No No
Fly backward Yes Yes No No No
Reverse Free –5 ft.
Turn Any 90˚/5 ft. 45˚/5 ft. 45˚/5 ft. 45˚/10 ft.
Turn in place Any +90˚/5 ft. +45˚/5 ft. No No
Maximum turn Any Any 90˚ 45˚ 45˚
Up angle Any Any 60˚ 45˚ 45˚
Up speed Full Half Half Half Half
Down angle Any Any Any 45˚ 45˚
Down speed Double Double Double Double Double
Between down and up 0 ft. 0 ft. 5 ft. 10 ft. 20 ft.


Only a mecha equipped with space skin (see Miscellaneous Equipment) can operate in outer space. However, the mecha’s operator takes a –4 penalty on all attack rolls and skill checks unless she has the Zero-G Training feat or has equipped her mecha with a zero-g stabilizer.

In outer space, mecha fly just like they do in the atmosphere, with three exceptions. First, all flying mecha improve by one maneuverability category (clumsy becomes poor, poor becomes average, average becomes good, and so on). Second, all mecha can ascend and descend regardless of the limitations on Table: Flight Maneuverability, and their speed is unchanged if they do so. Finally, all mecha can hover in space and need not maintain a minimum forward speed.


Whenever you confirm a critical hit against a mecha, you may choose to roll percentile dice and consult Table: Mecha Critical Hits instead of dealing the normal critical hit damage for the attack. However, you must accept the results of the roll, even if those results are less than desirable.

Table: Mecha Critical Hits
d% Roll Effect(s)
01–15 Normal damage, crew dazed
16–35 Normal critical hit, crew dazed
36–45 Normal critical hit, mecha knocked prone
46–50 Severe critical hit, crew dazed, mecha stunned
51–55 Severe critical hit, mecha knocked prone
56–60 Crew hit (normal damage)
61–70 Normal damage, equipment damaged
71–80 Normal damage, equipment destroyed
81–90 Normal critical hit, slot damaged
91–100 Normal critical hit, slot destroyed

Normal Damage: The attack deals normal damage (do not apply critical hit multipliers).

Crew Dazed: Each crewmember aboard the mecha, including its operator, must succeed on a Fortitude save (DC 15) or be dazed for 1 round. Unable to act, a dazed character can take no actions, but still retains his or her full Defense.

Normal Critical Hit: Roll critical hit damage normally.

Mecha Knocked Prone: The force of the attack knocks the mecha prone. All crewmembers and passengers aboard take 1d6 points of bludgeoning damage as they are knocked about their cockpits. A prone mecha takes a –4 penalty on melee attack rolls and can’t use thrown ranged weapons. The mecha gains a +4 bonus to Defense against ranged attacks, but takes a –4 penalty to Defense against melee attacks.

Standing up from prone is a move action that provokes attacks of opportunity.

Mecha Stunned: The mecha automatically drops what it is holding and can take no attack or move actions for 1 round. While the mecha is stunned, apply a –2 penalty to the mecha operator’s Defense (even though the operator is not stunned).

Severe Critical Hit: Roll critical hit damage using a x5 multiplier instead of the weapon’s normal multiplier.

Crew Hit: The attack bypasses the mecha’s armor and superstructure. Apply normal damage to one crewmember or passenger (determined randomly), ignoring the mecha’s bonus hit points.

Equipment Damaged: One piece of equipment (attacker’s choice) is damaged and ceases to function until repaired. It can be a flight system, sensor system, defense system, weapon (handheld or integrated), or miscellaneous system. Repairing a damaged system requires 1 hour of work and a successful Repair check (DC 20).

Equipment Destroyed: One piece of equipment (attacker’s choice) is destroyed and ceases to function. It can be a flight system, sensor system, defense system, weapon (handheld or integrated), or miscellaneous system. A destroyed system cannot be repaired, only replaced.

Slot Damaged: One of the mecha’s equipment slots (attacker’s choice) is damaged. Any piece of equipment wholly or partially installed in that slot will not function until the slot is repaired. Repairing a damaged equipment slot requires 1 hour of work and a successful Repair check (DC 25).

Slot Destroyed: One of the mecha’s equipment slots (attacker’s choice) is destroyed, along with any piece of equipment wholly or partially installed in it. Rebuilding a destroyed equipment slot requires 12 hours of work and a successful Craft (mechanical) check (DC 30).


Mecha only provoke attacks of opportunity from creatures of their own size or larger (including other mecha) when they fire a ranged weapon in a threatened area.


Any piece of mecha equipment integrated into a mecha’s hand slot—and only the hand slot—can be stowed magnetically against the mecha or in a storage compartment as a move action. This frees up the hand to perform more delicate manipulation (such as opening a door or pressing a button) or grabbing another piece of mecha equipment.

A mecha may have more pieces of equipment for its hand slots than it has hand slots available; it just can’t use them all at once.

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