It's an EOS Fork, and the protocol is cored on improvements in game distribution. Consider it a tokenized Steam (not STEEM) with all the added features described in the article.

STEEM enables content UIs which may be used for game distribution, but it lacks the developer/publisher partnerships that Ultra has and it also lacks the gamer and game dev-specific benefits Ultra is pushing. This is a key example of how specialization leads to competitive advantages. Ultra aims at one market whereas STEEM is designed to target any content; the specialized platform will naturally have more market-specific advantages.