Sonic, in Green Hill Zone, collecting rings, defeating bad guys... but what's this? Levelling up? Turn-based battles?! The whole world has gone topsy-turvy... and its great! Players take control of Sonic via the DS' stylus, pointing where you want him to go - very similar to the controls of Link in Zelda: Phantom Hourglass.

The title's story initially concerns the kidnapping of Knuckles, with a wider threat being the appearance of a mysterious new race named the Zoah. The game world, in which players begin once again located in the classic Green Hill Zone, is largely 2.5D. Sonic and other characters are rendered in 3D as they move around pre-rendered toon-style 2D backgrounds. If you approach one of the many enemies moving around the map (wild animals, evil sentry bots, etc.) then you enter the battle mode, which is in comparison completely 3D.

The top screen shows a map of the region - with grey areas for unvisited sections.

While navigating around, Sonic will encounter items and locations in the map only accessible via certain moves, some of which are character specific and controlled by on-screen buttons. Nearing one of those classic loops on screen brings up the button to dash round it, Sonic stylee. Nearing a friendly NPC brings up an on-screen button to begin dialogue with them - which can result in handy information or a the chance of a side-quest. Other map features include gaps needing to be hovered over (hmm... sounds like a job for Tails!) and other such blockages which limit your way - but need to be remembered for later when more allies join your party.

Once a character has joined, you can switch to control whichever one you please, which is necessary for using the special abilities of specific characters to navigate past those blocks in your path. It is also required so you can position each member of your party in a certain place - on pressure switches, for example, to solve a puzzle. In the opening section of the game, we played as Sonic, Amy, Tails and Rouge, with other favourites such as Knuckles, Shadow, E123-Omega, Big the Cat and Dexter (Amy's new boyfriend) also set to be controllable later in the game. Ed. We've just heard from Sega that we obviously heard wrongly, and that Dexter is not playable. In fact, "he might not even exist."

Team tactics: manoeuvre your crew into position to solve puzzles.

After the Green Hill Zone area, players progress on to recognisably themed areas such as Central City, Angel Island, the Mystic Ruins, Metropolis, the new Blue Ridge Zone - and that's just in the story's first act (the second of which is set in another dimension). Each area is large and free-roaming, with shops and other buildings to enter inside and explore. To complete the game, each area will need to be revisited to collect everything you need when you have additional abilities.

The animations throughout are fluid, with some nice graphics during fights, as Sonic and his party (of up to three other allies) face off against many enemies simultaneously. And after encountering Chaos, you can equip them to a character for special support during battles - some providing healing capabilities, others boosting your attack stats or providing a shield from enemy hits.

In each round of the turn-based battle gameplay, players have to choose whether to either attack, defend, use an item, flee or perform a POW Attack - a super powered move which you control via the stylus. Each POW Attack requires you to adhere to the on-screen techniques you must perform with your stylus to power up the move further. The more accurate you are, the more powerful your attack becomes.

Battle mode: an early battle against wasps. What is it with wasps? Reminds us of Metroid Prime all over again.

At the end of battles the player comes to a results screen, where you are given a grade for the battle based on how well you performed, and receive experience points for all your participating characters. Gaining enough boosts you up a level, at which time you can choose to increase the either your attack/defence/special or luck stats for use in further fights, as well as the ability to upgrade or obtain new POW Attacks.

The title does not feature wireless battling - the game plays as definitely more of a single-player story driven experience. Players can however link up their DS with a friend to trade Chaos they have hatched. Speaking of how the game plays - imagine a game along the lines of Paper Mario, add a tad more free-roaming, and you have the title's style pretty much pinned down. The game hasn't got the same deprecating self-referential humour of the Nintendo series, though you do have the ability to unleash the full potential of Sonic's sarcastic retorts which raise a chuckle. When speaking to others, players can choose how Sonic replies - for example with a simple reply, a pertinent question, or the opportunity for Sonic to instead unleash a scathing put-down if you're feeling rude.

And that's 'happy' Sonic. Poor Amy...

Bioware's Sega game is far from your average Sonic title. Make no mistake about it, Sonic Chronicles: The Dark Brotherhood is an RPG through and through. But if any genre haters are put off by this, they will be missing out on what is shaping up to be a unique Sonic adventure, and a genuinely fun game to boot.

The title isn't due out until September, and even that date is still tentative. But rest assured, we'll be keeping a close eye on this one over the next couple of months...