Thanks Merlkir. Tools? There is a lot of blocking in using the chalk and crayon tool. Line work fluctuates between pencil and inkline tool. Then there's a fair amount of shadow and colour variation laid down on layers of watercolour. The textural elements (particularly on the frozen water) were either just painted or introduced using a stencil made from a picture of a stoney surface, transformed to be much wider than it was tall.