Aye, you do need an Origin to play the game - much like the Spellbook you need to buy in Splinterlands. Other than that, everything is free though and you won't have to spend any more money if you don't want to.

There's a free version of the game if you want to give it a shot first. Keep in mind though that it's an early Alpha build, so expect many loose ends and not much of an explanation. We are expecting the release of the new version (Version E) pretty soon which should be a lot more feature complete.