This paper model is a Orc Deff Dread, based on the game Warhammer 40k. The Ork Deff Dread is a large Ork combat walker that is essentially a cross between an Ork Killa Kan and a Space Marine Dreadnought. The machine is smaller than an Ork Stompa, but is larger than a Killa Kan.
The Deff Dread is also capable of carrying up to four weaponised arms. Also like a Dreadnought, a Deff Dread's Ork pilot must be cybernetically hardwired into the machine. As a result, the construction of a functional Deff Dread requires the skills of both an Ork Mekboy and a Painboy.
When it is possible to craft a Deff Dread many Orks volunteer for the process since it will allow them to essentially become one of the biggest and most powerful Orks in the clan. Deff Dreads are also popular with other Orks since their immense destructive capacity, large number of weapons and tendency to stomp things to death lie at the very heart of what defines Ork "kulture." No two Deff Dreads appear alike but each is usually crudely painted and covered in spikes, skulls and the decaying bodies of slain Ork foes rotting on spears as is central to all Ork decorating schemes.
A Deff Dread is normally armed with two large claws or saws, Burnaz, Big Shootaz, Rokkit Launchas, Skorchaz and Kustom Mega Blastas. Deff Dreads are rare Greenskin war engines and will cost an Ork Warboss or Warlord around a hundred teeth to build and/or purchase from another clan. Orks often paint skull-like devices or add large Ork skull masks covering the front of this war machine.
You can download the paper craft model here: Warhammer 40K - Deff Dread Free Paper Model Download [Template]