The standard Swarm missile was developed in 2621 as part of an attempt by the Terran Hegemony to replace fragile and sluggish standard artillery pieces with more sturdy and mobile BattleMechs with specialized LRMs. The Swarm missile was intended to recreate area denial/splash damage ability of artillery shells, each missile releasing a "swarm" of submunitions which attack the primary target and any adjacent targets nearby.
Ignoring their higher cost, Swarm missiles remained task specific loadouts because the missiles would indiscriminately target any nearby unit, whether friend or foe, falling out of favor as the technological decline of the Succession Wars forced 'Mech combat onto short ranges and increasing the odds of friendly fire strikes. With both the Helm Memory Core and the Clan Invasion, the Federated Commonwealth and Free Worlds League each attempted to revive the technology with New Avalon Institute of Science reintroducing the standard Swarm in 3053, while FWLM focused on attempting to develop a variant of the Swarm missile which only attacked the enemy, resulting in the Swarm-I in 3057.
The Swarm-I is roughly similar to conventional Swarm missiles, but includes a IFF (Identification: Friend or Foe) detector so as to target only enemy units. However this modification is not foolproof, with the chaotic nature of the modern battlefield throwing up conflicting signals, active ECM Suites blocking the detector outright and damage to a friendly 'Mech or Combat Vehicles electronic systems preventing the broadcast of a IFF signal will cause a Swarm-I missile to act identically in such instances to a standard Swarm with all the drawbacks.
- Technical Readout: 2750, p. 40, 91
- Technical Readout: 3050, p. 216
- Field Manual: Free Worlds League, p. 137
- BattleTech Master Rules, p. 132