One of the most notable IIC BattleMechs, the Marauder IIC is based upon one of the most iconic 'Mechs in existence, the Marauder.
Touted as one of the most effective 'Mechs of all time, the Marauder saw wide usage during the Star League era by all the Great Houses. The design was also much favored by both the Star League Defense Force's Regular and Royal unit as well as its famed Gunslingers, with many examples taken on Operation EXODUS. The belief that the Marauder was a precursor to a new 'Mech design paradigm disappeared in the Inner Sphere as the Succession Wars dragged on; however, in the same year as the Second Succession War broke out the Clans developed an advanced refit of the venerable design later dubbed the Marauder IIC, utilizing technology already far in advance of that rapidly disappearing in the Successor States.
It is to the credit of its original engineers that no production variants of the Marauder IIC appeared until a wellspring of new technology emerged in the 3050s and '60s, with Clan Star Adderintroducing a visually refreshed model carrying the then-newly developed Heavy Lasers that quickly spread to the Cloud Cobras, Goliath Scorpions, Snow Ravens, Blood Spirits and Diamond Sharks. The efforts of the mercantile Sharks would result in the further spread of the design to the Inner Sphere-based Invading Clans, followed by Clans Jade Falcon and Ghost Bear introducing new Marauder IIC variants and constructing new productions lines for them on Sudeten and Satalice respectively during the Word of Blake Jihad. [Source: sarna]
You can download the papercraft model here: Classic BattleTech - Marauder IIC Free Mech Paper Model Download