Tile-based CRPGs have been doing that for years with smaller, 2D worlds, but taking those concepts into the interactive intimacy of a free-roaming 3D experience raised the CRPG bar as much as Ultima Underworld did.

Fiction filling the opening pages of the manual layout is a familiar starting point that Elder Scrolls fans will immediately recognise – a captured prisoner. In Arena, you languish in a dungeon beneath the Imperial City, where careless exploration could easily kill you even before beginning your epic quest to find the pieces of the Staff of Chaos and end the rule of the usurper hiding in the Emperor's skin, Jagar Tharn.

18 classes await in Arena, along with D&D-like stats to shape their your character from one of the eight races in the game. Or, borrowing a page from Origin's Ultima IV, a series of questions suggest which class will be best for the player. I remember spending an hour or so carefully mixing different classes and races together, testing them in the opening dungeon against sewer vermin, and then starting over again to try another class and mix of statistics.

Despite the Ultima IV inspirations, there's no alignment or strict moral fibre tying players' hands. You're free to bash down doors in the middle of the night to break into stores, steal everything and kill the guards on the way out with the loot if you want, while searching for a way to end Jagar Tharn's rule.

Combat appears to be simple button-mashing, but hides some unexpected depth. Melee attacks are done by holding the right mouse button and moving the mouse across the screen. Each movement executes a different type of attack: moving sideways leads to a slash, while a vertical movement results in a thrusting attack. Attacking at the same time as your enemy will parry the attack.