
The B configuration of the Adder was introduced by Clan Star Adder in 3010 alongside the OmniMech chassis. It trades away the twin ER PPCs of the Prime configuration to carry a more varied set of weapons that maintain the ability to be engage at long-range but trade away damage potential in exchange for a more manageable heat curve.
Read This First
- Maneuver to engage targets at 10-14 hexes. Getting closer is risky due to your relatively slow speed and inability to torso twist.
- Hold fire with one medium laser every other round to manage heat levels
- Rough terrain can slow you down and make you an easy target
Adder B
- Role: Sniper
- Tech Base: Clan (3010)
- Chassis: 35 tons (Endo Steel)
- Movement: 6 / 9, XL
- Armor: 115 (Ferro Fibrous)
- Heat Sinks: 10 (20)
- Weapons:
- Large Pulse Laser
- ER Medium Laser × 2
- LB 5-X AC (ammo: 20)
- Flamer
- Equipment:
- CASE
- Design Quirks
- Narrow/Low Profile
- No Torso Twist
- Cost: 7,042,866 C-Bills
- Battle Value: 1,422
Mobility
The Adder has relatively poor mobility for a light ’Mech. Its 6 walking MP and 9 running MP are just below average, but it lacks jump jets. In the open, it can run fast enough to gain a +3 target movement modifier, but rough terrain can drastically slow it down.
Durability
The Adder offers good durability for a light ’Mech. Its armor is 97% of the maximum for its tonnage, and the Narrow/Low Profile quirk allows that armor to take more hits than it otherwise could. Having an XL engine does mean that it is more likely to suffer engine damage. The B configuration carries one ton of ammunition in its left arm meaning that a critical hit has a 14% chance of triggering an explosion. Such a blast will cost the arm, but CASE will prevent any damage from reaching the torso.
Weaponry
At long range, the B configuration can make use of its LB 5-X autocannon and pulse laser at ranges as long as 24 and 20 hexes respectively. Depending on the type of ammunition used for the autocannon, both of those weapons can potentially have improved target numbers making them more accurate even at those long ranges. At 15 hexes, the Adder B can bring its two ER medium lasers to bear. Its final weapon is a short-range flamer that offers a potent anti-infantry option.

The minimum range of the LB 5-X autocannon means that the peak expected damage output for the Adder B is at a range of 4-5 hexes. In combat, a MechWarrior can decide whether they want to fulfill a longer-range sniper role at 14 hexes or close to within 10 hexes in order to get more accurate medium-range shots with the two medium lasers. The closer range is higher risk since incoming fire will be more likely to hit the Adder, but allows for more damage to be inflicted as well.
The B configuration suffers from restricted firing arcs. The large pulse laser and autocannon are arm-mounted, but the medium lasers and flamer are restricted to only the forward firing arc. Unlike the Prime configuration, the B cannot flip its arms to cover the rear firing arc because its right arm is equipped with lower arm and hand actuators.

The only weapon that uses ammunition in the B configuration is the LB 5-X autocannon. It carries 20 shots for it, so a MechWarrior generally does not need to worry about running out of ammo in a single battle. That is only one ton of ammunition though, so it can carry either standard or cluster rounds but not both. Before a mission, a MechWarrior should consider whether they expect light, fast targets or more heavily armored opponents and then choose the most effective ammo option.
Heat Management
The Adder B has a much more manageable heat curve than the Prime configuration, but it is still at risk of overheating. It carries 10 double heat sinks, but its weapons can generate 24 points of heat. In order to stay cool, a MechWarrior can fire the autocannon, large pulse laser, and one medium laser every round. Then the second medium laser can be fired every other round, and the flamer reserved for only special cases such as taking out conventional infantry.

Brawling
The B configuration’s complete right arm makes it better in a fistfight than the Prime configuration, but it is still better off staying at longer ranges. The right punch can deal 4 damage, but doing that requires not firing the more effective large pulse laser. The left arm lacks lower arm or hand actuators, so it can only deliver a feeble 2 damage punch with a +3 target number modifier. When kicking, the Adder can deal 7 damage.
OmniMech Chassis
As an OmniMech, the Adder can be re-configured between missions. It has 16 tons of available pod space in its side torsos and arms. One place where it lacks some flexibility is the flamer in its center torso that is fixed equipment. None of the B configuration’s heat sinks are in pods.
Capacity | 16.0 tons |
Head | none |
Center Torso | none |
Right Torso | 5 slots |
Left Torso | 5 slots |
Right Arm | 7-9 slots |
Left Arm | 7-9 slots |
Right Leg | none |
Left Leg | none |
The Adder B can carry a unit of battle armor, but it does not excel at the role. It generally wants to maintain more range with its targets and carrying a unit of 5 suits means that it sacrifices the ability to fire both of its medium lasers.
Cost & Upkeep
The Adder makes use of an XL engine, ferro-fibrous armor, and endo steel, so it is fairly expensive for a light ’Mech. The B configuration also generally requires one ton of ammunition to be replaced after each engagement.
When using the Warchest Point system, these are the expected costs for the Adder B:
Action | Clan Cost | Inner Sphere Cost |
Purchase | 700 SP | 1,400 SP |
Armor Repair | 35 SP | 70 SP |
Structure Repair | 70 SP | 140 SP |
Reload | 10 SP | 20 SP |
Reconfigure | 9 SP | 18 SP |
Miniature
A plastic miniature for the Adder Prime is included in the Clan Invasion box set. It can be used to represent any configuration of the Adder.