This mech paper model is Fafnir, intended to become Defiance Industries of Hesperus' flagship BattleMech, from the video game MechWarrior 4, the papercraft is created by BLaaR. The size of finished model is about 288 (H) x 265 (W) x 193 (D) mm.
The slow assault design serves as a platform for the pair of "Thor's Hammers". The Fafnir is built on a lightweight Foundation Type 220 Endo Steel chassis that is capable of supporting the Fafnir's massive weapons payload and armor while weighing half as much as a standard chassis. To power this massive 'Mech, a Vlar 300 fusion engine gives the Fafnir a top speed of 54 km/h. The Fafnir is protected by nineteen and a half tons of Durallex Special Heavy V2 armor, giving it almost as much armor as the entire mass of some light 'Mechs. The Fafnir has CASE in both of its side torsos to protect it from secondary damage if one of the Heavy Gauss Rifles are damaged. Finally, for protection from enemy electronic warfare systems, the Fafnir has a Guardian ECM Suite. [Source: sarna]
You can download the papercraft model here: MechWarrior 4 - Fafnir Free Mech Paper Model Download [Skins]