Drothmar is effectively the "Death" in the bionicle culture. Much like the Death in Terry Pratchett's Discworld novels (You know...THE ONE WHO TALKS IN CAPITAL LETTERS), Drothmar ushers bionicle spirits into the next realm.
However, Drothmar does not have a sythe, billowing black cloak, white horse named Binky, or a skeletal rat companion. He has shining metallic armor, twin spear/sword thingies, a skyboard made up of shards of protodermis and whatever bionicles have as bones (Probably just the outer armour, like an exoskeleton). His mask lets him levitate, so the board, called toothrend, is really just for show.
Drothmar is a makuta-like being. He is energy wrapped up in a metal armour shell. However, he is almost as old as Mata Nui (The islant that is).
A shot I accidentally made with the flash on...Whoops!
Cool! And yes, Toa and Matoran are beings of organic protodermis encased in armor, while Makuta have a greenish gas within them. Nice work, though the shoulders are a bit wide as compared to the lower torso. Overall, very good!