Never having worked in washable markers where I add water to them, I thought I'd do some testing.
First, sketch an imaginary magic horse in graphite and then color with markers. Use a brush to add water:
|Get the colors down.|
Next, more layering and blending:
|Add the eyes :-)|
Then details with graphite and charcoal:
These washable markers are a bit difficult to blend using water but they are easy to clean up and very inexpensive. This was a fun experiment.