Bellatorus is obviously inspired by trading card games (TCGs) like Magic: The Gathering, but it isn't a -trading- card game exactly; you get all the (virtual) cards with the game (and can download more from the developer's site) and edit decks with the provided editing utility--then play out games, either against remote opponents or an AI.
In other words, all the cards are available to you at all times, and you don't have to pay for more.
Unlike Magic, Bellatorus doesn't have land cards. Instead, the three resources in the game (crosses, skulls, and lumber) are produced by three different kinds of workers (priests, liches, and workers). You can hire more worker on any turn (up to 3 of a single type), but of course lose your opportunity to play a card on that turn if you do. In addition, each type of worker requires a building for support (churches, graveyard, or lumber mills)--each supports 5 workers of the same type--and building a new building takes a turn. And you can spend a turn "working" to produce resources. One nice fillip; you can discard a card for a replacement on a turn you spending hiring, building, or working, so if you have no useful card to play right now, you can do something else helpful.
As in Magic, your ultimate objective is to defeat your opponent, in this case by reducing his Tower to zero points. Attacks first do damage to opposing "walls" and then to "towers". Many cards allow you to increase your walls and/or towers; others deliver an attack; others affect your (or your opponent's) strength in terms of workers or constructions or resources.
A nicely rendered 3D screen, depicting your tower and walls and the constructions you own, animates during play, giving visual feedback to the strength of both sides, as well as the strength of their towers and walls; UI is quite intuitive, and a nice tutorial teaches the game quickly and well.
The single-player version is engaging, but in addition, Bellatorus supports both LAN and Internet play.
As it is, we think Bellatorus is a pretty strong game--but after a few plays, there's definitely a feeling that you'd like to have more variety in cards, and possibly a few additional strategic elements to add complexity to play. It does seem like the developer is planning on updating it continuously, and what's there now is certainly a sound structure to build on -- but it isn't yet the game it might become. Worth playing the demo certainly -- and possibly worth buying, both for what it is now, and to invest in the larger game it has the potential become.