On the multiplayer front, players will be able to visit other player’s homes. Elsewhere there’s co-op, leaderboards, and the ability to create custom dungeons – also, dungeons in the open-world are randomly generated – and a competitive mode Players vs Players vs AI (PvPvA?).
You can read all of the finer details about Umbra over on the Kickstarter page. In the meantime, keep it glued to IGN for all your PC gaming needs.