Nice work so far. I like the style. One option I'd really like to see in the future is an export/import button for save files if possible. It's just nice to be able to clear browsers and still keep the progress conveniently.
Your idea of characters evolving into 'better' classes sounds great as well. In that regard I'd love to see a real mage join the ranks some day with a classy pen&paper style lighting strike attack to support the team. *Thumbs up*
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