There's a certain charm to a game that can be played using just the mouse. Titan Quest is one such game, offering an epic adventure, hordes of mythical creatures, impressive production values, and a refreshingly simple control scheme. The mouse-driven RPG is a genre that most people will link with Blizzard's Diablo series, and while Titan Quest clearly isn't an official successor, Iron Lore have mimicked the much loved series well enough to please anyone wishing that Blizzard would hurry up with the true sequel.

If you're unfamiliar with games of this type, they're very simple, but utterly addictive affairs. Viewed from an overhead perspective (you can zoom the camera in, but you can't rotate it), you use the mouse to navigate your character around the diverse environments, clicking on an enemy to attack it, clicking on an item to take it, clicking on a chest to open it... you get the idea. The keyboard comes in handy too, for quick access to potions and abilities, but for the most part you can sit back and enjoy the simplicity of it all.

For an RPG there's not as much of an opening story as you might expect. Titan Quest focuses heavily on combat, and throws enemy after enemy at you, with the story taking somewhat of a backseat. A number of Greek titans have escaped from their eternal prisons, only to wreak havoc on all men who worship Zeus and the other Olympians who imprisoned them. A hero is needed to defeat the rampaging titans, so up you step. If you're expecting a character customisation system similar to Oblivion, think again, as your appearance isn't given much attention.

Before you start on your adventure you must choose a male or female hero and then the colour of the tunic that he or she wears - that's as far as character customisation goes. It's not as bad as it sounds, as the camera is often too far away to make any advanced customisation worthwhile, and various armour items eventually create a look that is unique to each player. At this early stage you don't even choose any abilities, with all that coming after you've tackled a few enemies.

Shortly after you begin you'll have earned enough experience points to reach level 2, and this is where you make your first choice as to what class of character you're going to play as. The usual mix of warrior, spell caster, and all that lies in-between is available, and as you level up you'll be given a number of points to bolster your most basic statistics (health, strength etc), but also points to spend on advanced abilities that suit your character.

Later on you'll get to choose a second mastery, giving your character an extra set of abilities, and should you become unhappy with the way you've spent your points, you can pay certain NPCs who will then let you reorganise you points however you wish. The primary and secondary mastery system, combined with the ability to re-spend your points if you become unhappy, means that you rarely find yourself wishing you could have different abilities while being unable to do anything about it.

Titan Quest is a long adventure, and keeping up with the main quest as well as side quests initially seems quite daunting. The quest screen makes this very simple, though, with all main story quests and side quests clearly laid out, with a logical and easy to follow progression system. You often have numerous quests going on at once, so being able to quickly glance at the current state of things makes everything very easy to follow.

While the quest system is handled very well, the inventory isn't so great. Throughout the game you'll come across thousands of items, be it money, armour, potions, weapons or relic shards. Every defeated enemy drops something, and chests often contain numerous interesting items. To begin with you'll go around picking up everything, but this 'take' mentality soon becomes impossible to sustain. As with most RPGs, you've got limited space in your inventory, so you must pick and choose the items you want.

It sounds simple enough, but a number of little things make the whole system rather annoying. Firstly, your inventory can't rearrange itself, which often results in wasted space, as items that could fit in a free space of three blocks, can't, because those three free blocks are dotted about the inventory grid - endless reorganising becomes a little tiresome. Secondly, while each item is compared to an item you're currently using when you're inside the inventory screen, you can't compare items in the game world to items you have in your inventory; not unless you add them to your inventory first, which may well require a re-shuffle, only to find that the item isn't worth picking up.

You get some idea of the item quality by the colour coding system the game uses, but even this doesn't tell you in detail if an item is worth picking up. Things are made easier once you increase the size of your inventory, and items such as relic shards can be used on weapons, increasing their power and freeing up space, but the system as a whole is far from ideal.

To aid your travels you have access to a compass map and a larger map screen. The compass map highlights key locations and quest items, and the larger map shows which areas you've explored already. Titan Quest's world is massive, and while walking around it is fine, you also can teleport from area to area using portals. Each city and safe area has its own portal, and once activated you can travel from one to another. You can also open your own personal portal, ideal for quickly getting out of a tricky situation or to save yourself a long walk. This portal then stays in the game world until you open it in a new location.

Battling through the game and taking on the powerful enemies is fun in itself, but it's made all the more enjoyable if played with friends. Up to six players can join you on your quest, and your character can move from single-player to multiplayer games. As well as the obvious advantage of having more characters to battle the enemies, the social aspect of adventuring takes things to a new level. Currently there's no way to set rules for how loot is collected, so items in the game world are open to be swiped by one character. This is an issue if your comrades are a little selfish, but on the whole people play to be part of a team.

Even though Titan Quest is viewed from a semi-fixed camera, the world often looks stunning. The opening environment sets the benchmark and it remains high throughout, with little touches like grass moving as characters move through it, and some excellent day-to-night lighting effects. Voice work and the musical score are also excellent, with every NPC offering a few fully voiced words. This splendour does come at the price of performance, though, with detailed areas often bogging down the frame rate on all but the most powerful PCs.

There's a lot of fun to be found in the single-player adventure, and playing with friends is a blast, but the included modding tools point towards an incredible lifespan for the game. The tools provided are apparently the very same that the developers used to create Titan Quest, and as such present wannabe level designers with everything they need. While too complex for most of us, the simple fact that such tools are included means that some great fan content is bound to be produced in the months to come.

Titan Quest doesn't really do anything new. What it does do is deliver a lengthy and hugely enjoyable single and multiplayer adventure, wrap it up with some stunning presentation, and make it accessible to almost everyone. Some niggles with the inventory system are a little grating, but it's easy to forgive a few slight oversights when the game as a whole is so well put together. There's the potential for new (free) content as well, making the game a must for all RPG fans.