As we wrote last week, you don’t need flashy graphics to create a great game: there’s plenty of retro entertainment to be had from the ideas behind old classics like Command & Conquer and the X-Com series.

If you prefer something even simpler, though, it’s a good idea to install Lines95. The Colour Lines-based game may look about as visually exciting as the old Windows Minesweeper, but it gets everything else right, being simple to learn, yet with real strategic depth that could take a very long time to master.

The core idea is very straightforward.

You start on a simple grid, with three coloured balls, and can move one of these to any of the empty squares in a couple of clicks. As long as the ball can get there in a series of horizontal or vertical moves, anyway (it can’t travel diagonally).

Three further balls are then added in random positions, and you can move any of these in the same way.

The aim is to create a line – horizontal, vertical or diagonal – containing five balls of the same colour. Do this, and you’ll score points, the balls are removed, and you’ll get another go immediately (that is, no extra balls are added). But the longer it takes, the more the extra balls begin to get in your way, blocking your movements and generally making life more difficult.

What’s the best strategy, then? A good place to start is by trying to look for and build as many three-ball lines as you can. Keep these open-ended, where possible, so you can add balls to either end of the line (if one end gets blocked by a new ball then you can always carry on from the other). And always look out for new possibilities: if a near diagonal has just popped up then you don’t want to miss it.

There’s a lot of depth, here, though, and plenty of room to learn. How much? Play your first few games and you can be justifiably proud of scoring two or three hundred, but experienced players can score many thousands. We’re not sure that we would have the patience for that – Lines95 is entertaining, but doesn’t have the playability of, say, Tetris, and it can become frustrating after a while. Still, if you like this kind of puzzle-type game then there’s a lot of fun to be had here.

Beware, though, there is just one possible issue: on one Windows 7 system we found the game had an odd audio problem, occasionally disabling sound on the PC. This may have been a local conflict, nothing to do with Lines95. But if it happens to you then you can restore normal working order by restarting the Windows Audio service (see the program’s download page for instructions), or just rebooting, and if you then turn off sound within Lines95 then the problem shouldn’t happen again.