Hi, I created a Reaper in Blender. It is already rigged and textured. For the Textures it may be helpful to have some basic Materail-Textures for the Metal, so that the Models look not too different. I already created some and if you like them I can share them. ;D
Based on the model, i uploaded two vids. In one animation i just let the legs move, to better support a moving body for aming in first person for example.
//Added: Run Animation:
Here is the Result: