This mech paper model is Grigori, one of the Word of Blake's new Celestial series OmniMechs designed by Doctor Devon Cortland from the game Classic BattleTech, the papercraft is created by Yogsolthan. The size of finished model is about 200 (H) x 207 (W) x 168 (D) mm.
The Grigori was added to the Word of Blake Militia's arsenal in late 3069 as Doctor Cortland oversaw the final production personally. It is constructed on a standard chassis, but makes use of eleven tons of Light Ferro-Fibrous armor, a light fusion engine, and an XL Gyro; as well as the small cockpit that is common to all of the Celestials. Like the other Celestials, the Grigori has a C3i Computer to help direct its fire. [Source: sarna]
You can download the papercraft model here: Classic BattleTech - Grigori Free OmniMech Paper Model Download