WHAT really matters when you slip the latest arcade conversion into DF0? Is it how good the original was, how good the Amiga version is or how faithful the conversion is to the money munching machine?

One theory states that any game which makes it to the arcade is going to be pretty hot. If it cuts the ice there, it should make a very playable game at home.

There is another theory that a game you want to spend 20 minutes playing in an arcade is not the same kind of things you want to take home with you.

And there is a third theory. This theory, which is mine, claims that a good game for a home computer would be one which was perhaps a little too complex for the arcades.

Xybots is that game. There is a lot of depth to the plot built on the age-old 3D maze. You run around a complex of corridors picking up coins, extra weapons and energy. A friend can join you wandering around the same maze with a separate 3D view.

While teamwork is the best way to take out the robotic monsters, especially if one of you uses a stun weapon, there is a race to the finish which will yield a bonus coin.

Money makes the game go round. At the end of each level you visit a shop. Here teamwork is really important. There are loads of accessories for sale. Some - like a higher level of energy, stronger shields and better weapons - only help one play. Others - like keys, and sensors which add detail to a plan-view map of the maze - help both sides. You can share and enjoy by giving coins to your comrade in arms.

Xybots was great in the arcades but there are things which thousands of pounds worth of dedicated hardware can do which an Amiga cannot. So something has to be sacrificed to effect the conversion. In the case of Xybots this is not very much. The game retains a high degree of accuracy, paying the price with speed. A lot of action on the screen slows things down, particularly when both players can see each other.

The attract screen animation has been retained but the scenes in the shop where one player waits for the other to finish have been cut. It is cute but no real loss.

More of a problem is the inability to turn and fire, imposed by having to use a standard joystick instead of the wacko arcade controls.

In the balancing act between playability and authenticity Tengen has scored a perfect 10.

I 'm Rock Hardy, me. This is me mate Ace Gun, reet. And we're 'ard us. (Switch to government-approved, BBC middle-class accent). OK, so they have stupid names, but they certainly need to be hard to take on the Xybots, vicious robots defending an underground complex.

The most obvious and interesting things are the 3D perspective and two player mode. The split screen gives both players an over-the--shoulder view of the characters they control This means you can see some way down the corridors as they taper into the distance. The players can move around with total independence of one another and, because the corridors run in all directions, they are able to turn through 90 degrees to face any which way.

The complex is divided into levels, each of which has one or more exit doors to the next level. You must battle to the door, picking up objects along the way to make the going easier. Exploring the complexes is made much easier by the map at the top of the screen, flanked by status information on the two players. The map identifies everything using colour coding and symbols.

There are two weapons: a forward-firing gun, and a zapper that freezes the robots for a time. However, nearly all the robots shoot back, damaging your shiled: rapidly with the nastier robots.

The objects in the complex include coins, energy capsules, keys and extra weaponry. The extra weaponry doesn't last very long but gives you impressive firepower for a time. Regular energy capsules are essential in the long war of attrition. Keys open up areas of the complex containing useful items and level skips. Coins are also important at the end of the level when entering the shop.

In the shop you can buy many supplies, such as increased shot power, better shielding, guard mappers, faster shots, keys and so on. These are vital for progressing through the levels because the opposition gets heavier and the maps get bigger.

If a player dies on a level it has to be restarted. Even worse is the confrontation with the Master Xybot which can send you back several levels. The Master Xybot appears every few levels and is no easy task to deal with.

The two player action in Xybots is amongst the best to be found anywhere: particularly because the two players can split up to clear out levels, so they do not always need to be in the same place. In the arcades it was not one of the greatest ever hits, but it translates very well indeed as a one or two player game.

As a coin-op, 'bots was an unusual game. Unusual both in the way that the game combined strategy to a maze shoot 'em up. Set in a space station of some description, you, and a friend if you so wish, play Major Rock hardy (!?!) and Captain Ace Gunn (!?!?!). These two dashing heroes have to move around the space station, killing all the evil robots that patrol the levels, collecting coins and extra weapons.
The coins allow you to improve the stakes at shops between levels. Here you can buy things like more powerful shots, slower loss of energy and a higher overall energy limit.

The game is viewed from second person perspective, from a point just behind your man and looking in the direction he is facing. The ground is set out as a grid, and the view only changes when your man moves into another square in the grid. Left and right make the man move to the left or right, side-stepping as it were. Forward and back make you run forward and backwards. To change direction, hold down the fire button and then move the joystick left or right. This rotates you through 90 degrees and comes in handy when faced with multiple direction attacks.

The 3D is very convincing. The sprite update is clean and some very clever maths have been sued to ensure that the positioning of the objects is 100% accurate. That way you and your partner can view different situations from entirely different locations.

Xybots is a maze game that on the later levels, will require a great deal of exploration. That is why two-player teamwork is vital, and indeed the game works best in two-player mode. Rarely has a two-player split screen game worked so well, and if you have any friend and a spare hour of five, I recommend getting them over to your house to play this.

The graphics are as close to the coin-op as you could wish. As I have said, the sprite update is perfect, as is the actual sprite positioning. The darkening of the corridors as they disappear into the distance gives a pretty good feeling of distance.
The sound, finally, matches up to the graphics perfectly. Bullet and explosion effects are great, and the radar works a treat. A droning sound gets louder as you approach something of value and quieter as you walk away.

I never thought much of Xybots as an arcade game. There was just too much thinking to do, and it did not really serve its purpose at all. After all, coin-ops are supposed to be a form of instant escapism, and Xybots just was not instant enough. As a computer game, however, it finds it mark. Involving and challenging, Xybots is a game very Amiga owner should consider having.

The Xybots are the latest villains in an ever violent future. A near- perfect race of robots they have an unhealthy thirst for power and it doesn't take the invaders long to set up their massive underground fortress and enslave all around.

To remedy the situation two galactic heroes, Major Rock Hardy and Captain Ace Gunn, are sent down to break into the city and decimate any Xybots within.

The fortress is made up of many labyrinthine levels infested with robotic Xybots and fellow guardians. Using a split screen the two laser gun-carrying fighters run through three-dimensional corridors. Rock and Ace can swivel around through 90 degrees by holding down fire with left/right. Enemy robots continually try to sneak up on them - 'danger arrows' indicate which direction they're in.

As well as standard laser some of their ever-decreasing energy. Take a hit and the energy goes down even faster, once out of energy a life is lost - a new one can be obtained by using one of nine communal keys. The robots consist of shielded droids with limited protection from attack, leaping fly guardians and unarmed but fast-moving droids.

As a last resort, a Zapper can be used to stun nearby robots, although this costs the heroes credits. Also, extra energy can be picked up along the way as well as coins which can be used in the end-of-level shop to buy energy pods, higher energy levels and the ability to lessen the ever-present energy loss. Weapon add-ons can also be bought to boost the gun speed and strength of fire and increase the strength of the Zapper.

Every few levels (starting from level ten) the master Xybot must be defeated to progress - if the heroes fail they're taken back quite a few levels.