This is Angron: Primarch of the World Eaters Legion from the table top game Warhammer 40K by GamesWorkshop. This was a conversion using various bits from other GW minis, plasticard, extruded plastic profiles, modelling bits and a lot of sculpted green stuff putty and Milliput Black. If I remember correctly he stands at roughly 54mm tall from foot to top of spikes. Below is a link to a showcase video and a few pics.
Just click the link below for a YouTube video: