The Exodus fleet carried large numbers of the Guillotine, a rugged Star League Defense Force design, away from the Inner Sphere to Kerensky's followers' new home beyond the Periphery. When Nicholas Kerensky had established his new society and retaken the Pentagon worlds with those disciplined forces, the newly formed Clans set about building 'Mech units, relying on existing designs for their blueprints. A large number of Guillotines found in storage on the Pentagon worlds of Eden and Circe were distributed among the Clans who maintained enclaves on these worlds. This sturdy, dependable design served in the front lines until the advent of OmniMechs, when the Guillotine was relegated to second-line and solahma units.
When the time came to produce new second-line 'Mechs, Clan Coyote engineers reworked the venerable Guillotine into a newer, more powerful design rather than inventing an all-new unit. Replacing the old Inner Sphere chassis with a Clan endo-steel chassis, the engineers freed up more space inside the 'Mech for weapons. Already satisfied with the ’Mech’s armor protection, speed and jump capability, the engineers concentrated on giving the Guillotine better firepower.
The Guillotine's main weapon was changed from a large laser to an ER PPC, and the arm-mounted medium lasers were replaced with two large pulse lasers. Two extended-range medium lasers and a Clan standard SRM-6 rack round out the Guillotine IIC's new weapons suite. To help the ’Mech dissipate heat from this load, standard heat sinks were replaced with sixteen Clan double heat sinks. The Guillotine IIC was officially unveiled in 2889.