Summary from their page:
Crimson Daggers is a free online community/study group focused on improving all around fundamental skills. Primarily we work within the realm of Illustration and Concept art.
They are a free study group for the hardcore artist or amateur dedicated to put in some serious effort to improve their work. Dave and Dan will critique and help you get better and they do this all on their free time which tells a lot about the kind of artists and people they are.
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