Myomer Accelerator Signal Circuitry
Introduced in 2740 by the Terran Hegemony, the Myomer Accelerator Signal Circuitry (MASC) is a piece of equipment that allows a BattleMech to move at twice its walking speed. However, actuators were not built for this kind of stress, and prolonged usage of MASC systems can damage the leg actuators of a BattleMech. Although this is unlikely to immobilize the BattleMech, the danger of destroyed actuators is enough for cautious warriors to limit their use in battle.
MASC was one of the many pieces of Star League technology that became LosTech in the Inner Sphere during the First Succession War, becoming extinct in 2795.
The Capellan Confederation would revive the technology to reintroduce MASC in 3035.
Meanwhile like many examples of former Terran Hegemony and SLDF tech the Clans never lost it and would refine the tech into a version taking up less space and weight vs the inner sphere grade original.
For Inner Sphere 'Mechs, MASC takes up a number of critical spots equal to a 'Mech's tonnage divided by 20, rounded up, and an equal tonnage. For Clan 'Mechs, MASC takes up a number of critical spots equal to a 'Mech's tonnage divided by 25, rounded up, and an equal tonnage. MASC is a single piece of equipment, unlike Endo Steel or ferro-fibrous armor, and the critical spaces must be allocated to a single location. Destruction of that location or a critical hit to the MASC will destroy the equipment rendering it unusable, though the mech will otherwise perform normally.
When a player first activates MASC, they roll 2D6. On a result of 3+, the MASC operates normally. On a 2, the 'Mechs leg actuators will suffer damage, the player must mark off a critical hit to every leg of the Mech. The second consecutive turn MASC is used, the target number increases by two, to 5. On the third turn, it increases to 7, and so on. If a player ceases to use MASC for one turn, the target number is reduced by two. So if a player uses MASC on consecutive turns, does not use it on turn 3, then wishes to use it on turn 4, his target number will be 3. If ever the target number isn't reached on a roll, add a critical hit to the mech leg before the Mech moves, use the critical damage to factor in the new walk speed, then double that, and apply any piloting rolls as normal during the move.
When it's successfully activated, the MASC allows the unit to run at double its standard walking speed (adjusted for modifiers such as damaged leg actuators, etc.) for that turn. Though obviously unreliable if used continuously, if used wisely it can have a devastating effect in combat.