Two Worlds is an RPG series for consoles that's had a few releases already, but this game for iOS only uses the same setting and assets as those titles. As you can tell from the title itself, it plays very differently from the third-person RPG. It's a castle defense game of a sort, but rather than building towers, you build out your army and forces, tasking your little soldiers with fighting incoming waves of bad guys.
The game plays sort of like the very popular Battleheart, though instead of directly controlling your troops, you're only placing them on the field in various spots available. You might put two melee fighters up front, for example, a priest behind them, and then two archers in the back to pump out ranged damage. As you fight, you win gold, and then can spend that gold to build more troops, upgrade the ones you've got, or even cast spells to heal your troops or attack the enemies.
The game is simple but really fun, and the polish is actually really impressive. Controls are not explained well, but the icons are clear enough that after a few rounds with the title, you will know what does what. And pitting two powered up soldiers and a hardcore fire mage against a wave of incoming baddies is very rewarding, once you've gotten to that point.
A recent upgrade added a few much needed tweaks, including Game Center integration and some various difficulty levels, and it also dropped the price of the game to just US $4.99. And that's not a bad price at all -- it's a little more expensive than most iOS games, but this is a quality experience. There is a lite version, though, if you doubt the price, but for castle defense fans, those who enjoy the Two Worlds series, or just anyone who enjoys a good fantasy-based tower defense game, this one's definitely worth checking out.