Yo! I checked out the forums just now and saw that you are/were looking for critiques...
well... here goes...
The first thing that caught my eye is your lineart... the lines look pretty shaky and unsteady. While that works in some parts, such as the torn mantle and the rags. It does not look good on parts with a smooth "straight" surface... such as the legs.
IF there is something supposed to disrupt the smooth surface such as scars, wrinkles, warts or whatever give them a little bit more detail, such as a shadow and/or a highlight, so that people KNOW that's an intentional detail, and not just a clumsily drawn line.
(Also: Why are the lines of the chain thinner than all the other lines?)
The geometric figures you used all look irregular... but not in a good way.
Take your helmet for example:
Helmets usually have one uniform shape that is symmetrical. A great helmet for example can be cylindrical but in that case it's almost always perfectly cylindrical.
The stones of door-arches too usually have the exact same shape.
Looking at the body of your character... well, it's supposed to be some skeleton/ghoul thing right? Next time you may want keep the picture of a human skeleton at the side as a reference... or maybe Raziel from the Legacy of Kain Game Series.
Regardless of whether you were going for a realistic look or an abstract one, there are certain details that just look wrong:
The shape of the hand... the absence of joints on both the fingers and the arm.
Lastly... I'd suggest you check out Adventure Time, or rather the way Adventure Time Characters are drawn... while I can't really tell what kind of look you are going for right now, I think the Adventure Time artstyle would be something you'd like to consider... or something you'd be good at.