The Mecha Action System v0.7

Mecha combat roleplaying.
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The Mecha Action System v0.7

Post by Tenebrae » 07/08/17

MAS v0.7

General Notes on the Mecha Action System
Like the Micro Action System developed for Thelus, the goal of the Vulcan Wolf MAS is to provide players with tactical options without having to keep track of their particular inventory of missiles or bullets or how many sandwiches they’ve got in their pocket. Aside from health, the only other things which are tracked are binary conditions. So a weapon doesn’t have 16 bullets, it either has ammo or is out of ammo for some reason.

As such the game will forgo elements of realism in order to provide a fun, playable experience. Sometimes it will seem like the field of play is small and mecha are fighting house-to-house, and other times it will seem like they are spread out over kilometers. Yet, mecha will move and fire across these arbitrary squares in the same way using the same weapons. You might wonder why only one type of missile may be loaded into an 8-cell VLS, or why, being so loaded, you can fire it a dozen times.

If you are wondering about these science facts, just repeat to yourself: it’s just a game, I should really just relax. With that said, the goal of the game is also to capture the general spirit in which these real world weapons are used. If you uncover some wrinkle about them that would add to the gameplay, do tell.

Virtual Tabletop
In spite of our attempts at simplicity, gameplay will still be relatively more granular and technically-minded than Thelus. That being so, gameplay will employ a virtual tabletop system. For various reasons, Tabletop Simulator was chosen.

Planning Phase
The planning phase of the game will take place asynchronously on the forums in the form of a forum adventure in the vein of “Problem Sleuth” or “Prequel.” Actions in these phases may take place in a short time in the game world, while in the real world they are played out in a leisurely fashion over the course of weeks. At the conclusion of the planning phase characters will equip their mecha with systems and enter the contact phase, where we will decamp to the Thunderdome and settle things with violence.


Systems are essentially abilities that mecha possess. In the Micro Action System of Thelus, they were called “Abilities.” Some systems are integrated into the mecha and other systems can be switched in and out of hardpoints. Some systems are unique to certain mecha and others can be traded between them on the fly. In addition to systems there are ‘extra actions', which is a catch-all for minor systems and pilot abilities.

By default, on a pilot’s turn he may use one movement system, one weapons system, and may take one extra action. They may also take any number of free actions. For example: a pilot may choose to move to cover (movement system), then use an optical camo system to establish an ideal pattern for that cover from the perspective of the targets (extra action), then launch an attack (weapons system). That would be the end of a well used turn. It is not necessary to take all of these actions on a turn, however; players are given lassitude so they can make maximum use of their turns where it absolutely counts, not so they can clog up the game with unnecessary actions when nothing is happening.

Use of Extra actions requires an Extra point. Players begin each game with one Extra point and one reserve Extra point. The Extra point recharges every turn an Extra is not used. The Reserve Extra is available at any time and may even be used out of turn, though not in direct response to an enemy action.

Other systems can be said to be passive and respond to enemy action, like defense systems. Their effects will be resolved by the ST where called for. By default, control over passive systems is whether they are off or on.

Systems that mecha can equip or which are integrated into them will be listed on their individual sheets. Systems which all mecha possess are listed in the Common Systems document. While the general rules may give illustrative examples, when it comes to the mechanics of play the system descriptions take precedent.

Health and Armor
Mecha have a single pool of health, representing the citadel. The citadel is the central core of the machine and contains the pilot seat, the Pulse Drive, the CPU, and other subsystems. More heavily armored mecha have greater citadel health pools. Generally a light mecha will have 8 health and a heavy one will have around 12 health. When citadel health is zero, subsystems inside of it become vulnerable. That includes the pilot, so perhaps you should consider advancing in the other direction. After the citadel health reaches zero, critical subsystems will begin to take damage. Though not all damage past 0 is to the cockpit, any damage to the cockpit will result in death.

Mecha also have an armor value which does not vary during play. It will be between 5 and 7. Weapons systems have a number of attack dice associated with them and must throw at least one die that is at least the armor value in order to do damage. For example: a mecha with 5 armor is attacked by a system with 2d8 attack dice. If these dice are rolled and at least one die is 5 or greater, the attack succeeds and the mecha takes all the damage. If neither die is 5 or greater, the attack fails and no damage is taken.

In play a mecha may have an Effective Armor Class (EAC) which is higher (or or rarer cases lower) than their base Armor Class, usually as a result of being behind cover or wielding a particular defensive system. Some enemies and player mecha will have higher EAC versus certain kinds of attacks or in particular situations.

Systems do not have health pools, but exposed systems may be targeted and destroyed in an all-or-nothing attack called a precision shot. Whether a Weapons System is capable of a precision shot would be outlined in its System description. Systems within the citadel or which are otherwise unexposed—for example, a back-mounted system which should not be vulnerable to a frontal attacker—cannot be targeted with precision shot.

Active Defense Systems
Active defense systems, such as small FELs ("S-FEL") and Super Sea Sparrow (”3S”) missiles, nullify the damage of incoming missiles by nullifying successful attack dice. Small FEL defense systems are not effective against large missiles. 3S missiles are, but typically may only neutralize one per turn.
Last edited by Tenebrae on 09/30/17, edited 15 times in total.

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Re: The Mecha Action System v0.1

Post by Tenebrae » 07/08/17

Moving Around

The game is played on a square grid. Each square is two units wide, so moving from one square to the next requires two units of movement. How many units of movement are available to a mecha depend on what movement system is in use. Moving up a level on a slope requires two movement units. Moving up a sheer vertical surface requires two movement units and Jump Jets.

There are three main types of movement systems. Some extra systems impart movement abilities, but their use is not considered as using a Movement system. Particular details regarding the quirks of individual movement systems can be found in the systems descriptors.

Walking Movement System
Walking movement systems are just as they sound. Grouped under this heading are also multi-legged mecha who would be more accurately said to crawl. They vary in speed depending on the design, but multi-legged designs do not need to spend additional movement to move up slopes.

While there is no penalty for turning, walking must be done facing forward. At the end of the turn, a pilot who has employed the walking movement system may choose his facing. Generally mecha using walking move at a rate of 6.0-10.0 units per turn—consult your character sheet for more detailed information regarding your specific walking system.

Rolling Movement System
Over solid, level ground such as roads or lava flows, a pilot may use the treads or wheels built into the feet of the machine. Rolling movement may be done forward or backward. Rates for rolling movement are typically 10.0 per turn.

Flying Movement System
Flying Movement enables a passage of a large number of units per turn and is not impeded by obstacles or terrain of any kind.

Impaired and Disabled Movement
Most systems, if they are struck by precision shot or some other ability, simply cease functioning. This isn't the case with movement. Disabling the movement system comes in three phases: first rolling or flying movement is disabled, then walking is limited to 4.0 units per turn, and finally the walking system itself is disabled.
Last edited by Tenebrae on 09/28/17, edited 5 times in total.

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Re: The Mecha Action System v0.1

Post by Tenebrae » 07/08/17

Weapons and Doing Damage

There are three types of damage: explosive, kinetic, and radiant. These distinctions will not be important, until they are. Most weapons will work on most enemies, unless they don’t.

Weapon damage is a fixed number (for example: 2) and is listed in the system description. What varies is whether or not an attack is successful. To determine the success of an attack, roll the weapon’s attack dice. If at least one of the dice exceeds the target’s armor class, the attack does all of its damage. Critical hit and critical chance rules are specific to weapons systems.

Dice for small missile volleys or large missile area damage work slightly differently. In these instances a handful of dice are thrown and each success is counted individually. So these weapons systems do a fixed amount of damage, but they issue multiple attacks and the success of each is independent.

In the documentation, attack dice which are volleys have a ‘v’ appended to them. So a volley of six d8s would be 6d8v.

Weapon Range
Weapon range is calculated just the same as movement, by counting the number of squares to the target. This is called ‘taxicab geometry.’

Ultra Range: 36 units
Long Range: 24 units
Close Range: 12 units
Melee Range: 2 units

Shooting Through Things
Sometimes it may be desirable to shoot something which is on the other side of a wall or other such obstacle. This is completely possible if the pilot has sighting information from a drone or another allied unit. Depending on the construction of the wall or barrier in question, this may add a point of effective armor class to the target.

Guns have magazines which may contain specific types of ammunition. For the sake of simplicity each magazine can contain only one type of ammunition, and changing types requires that the entire magazine be changed. A weapon will be assumed to be able to fire unless it has been rendered out of ammunition by an ability or disabled by enemy action. Guns have the kinetic damage type.

Two kinds of lasers will be relevant to gameplay. Small lasers, which are either based on free electron or fiber laser technology, are used as part of an active defense system and their effects are dealt with as passive systems. Large lasers can be used to attack targets and have the radiant damage type.

Missiles may either be launched from a forward-facing Armored Box Launcher (ABL) or from a Vertical Launching System (VLS). A VLS is mounted on the back of a mecha so it can be safely ejected in the event the munitions begin to cook off. Missiles have the explosive damage type.

Small missiles are mounted in ABLs and are launched in volleys. They do damage to a single target.

Large missiles are mounted in VLSs do comparatively less damage, but they do area damage in the target square and the squares adjacent.

Melee Weapons
Durable and effective edged weapons are out of the reach of current technology, limiting these options to crushing implements. In anthropomorphic robots, the fist has been hardened so as to be used as a hammer-like weapon. On heavier designs, an electromagnetic pile driver can be used either as an integrated secondary weapon, or as a main weapon mounted on a hammer.

A handful of bladed weapons exist. Melee weapons have the kinetic damage type.

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Re: The Mecha Action System v0.3

Post by Tenebrae » 07/14/17

Other Weapons and Buildings

In addition to mecha the standard array of traditional units may be on the field. The enemy may also be classed into these categories.

Light Units
AC: 1-2
HP: 1-2
Movement: 2.0 to 12.0

Light units are things such as light infantry or unarmored vehicles such as trucks. While these haven’t got much health or AC, they can carry portable weapons which are capable of harming mecha under the right circumstances. While infrantry obviously has no armor class, they may have effective AC due to being inside of a building or behind cover.

Armored Vehicles
AC: 2-3
HP: 1-3
Movement: 4.0 to 8.0

Armored vehicles include APCs and launchers. APCs may discharge light units with their own weapons, and launchers may carry any kind of missile. Launchers may prove a great danger, but are easily dealt with when found.

AC: 3-4
HP: 3-4
Movement: 6.0

Tanks are traditional tracked armored units. Their smoothbore cannons have the same diameter as those wielded by smaller mecha, but often have lower caliber, lower muzzle velocity, and inferior stabilization. As a result, they tend to do slightly less damage when fired. Their armor and general survivability is lower. They are, however, nothing to write off.

AC: 2-5
HP: 3-??

Occasionally, ships of the Carrier Strike Group will be on grid. In these cases they are vulnerable to surface attack. In rarer cases, enemy ships may be present.

Structures come in three broad classes: regular, reinforced, and protected. The most effective damage type against most structures is explosive.

Attacks which penetrate cleanly through a building and do not target its structure do not drain a building’s health. Only targeted attacks against that building and explosive area damage will do damage to a building.

Regular Structures
AC: 1
HP: 1-3

Reinforced Structures
AC: 2-3
HP: 3-5

Protected Structures
AC: 3-5
HP: 3-6

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