Earth Shaker is a puzzle game that was originally released for the ZX Spectrum in 1990, and was written by Michael Batty. Michael kindly gave us permission to release this version for the Xbox 360, which contains all his original levels, graphics and music, and has been extended to incorporate a level designer and replay feature.

The idea of the game is to collect all the diamonds on each level and get to the door before the time runs out. There are many things to help and hinder you on the way, including boulders (don't get crushed!), fire (don't get burnt!), bubbles, teleports, jumping jelly beans, forcefields, elixirs, reversed gravity and much more.

Earth Shaker was released for the Xbox 360 via Xbox Live Indie games in February 2010, and remained available until the Xbox Live Indie Games service finished in October 2017. The game is therefore no longer available, but we are working to release it for other platforms in the future.

Here are some screenshots from the game. Click on them to view larger versions. You can also download the soundtrack to the game for free here.

The first level of Earth Shaker is also the easiest. Here you'll be introduced to walls, earth, boulders, diamonds, doors, bubbles, jelly beans and fire, and it's a good opportunity to experiment with how these items work in the game. The only thing you really have to be careful of is the diamond at the bottom of the level that is sitting on top of the fire - make sure you don't get crushed by the boulder above it when you collect it (the easiest way to achieve this is to dislodge the boulder first).

Another easy level. Here you'll be introduced to the forcefield (albeit very briefly - as soon as you move it will be destroyed as a boulder immediately falls on the monitor) and the need to remove both boulders and bubbles using fire. Most of the bubbles just get in the way but shouldn't cause you too many problems, just be careful of stray items falling on your head or blocking the bottom passageway.

This level sees the introduction of reversed gravity, although apart from the fact that the gravity sticks are blocking diamonds, they are not strictly necessary to completing the level itself. The level is laid out so there are spaces above most of the boulders and diamonds, so the effect of the gravity can be clearly demonstrated. Just be careful to stand somewhere safe when the gravity returns to normal, and make sure you don't trap any diamonds in a boulder avalanche.

Level 4 is the first level where the solution is not immediately obvious. Teleports are introduced here, and tempting though it may seem, walking straight into the one that is immediately next to you at the start of the level is a fatal mistake! You must first remove the forcefield, then it's a case of using the various teleports to move through the different "rooms" in the middle of the level, and back to the outside to get the door. This is also the first level that you must master the art of running from falling objects.

Nothing too complicated here - this level is basically just a big maze with a lot of diamonds to collect. The teleport is not strictly necessary (but remember to remove the forcefield first if you do use it) but is best used as a shortcut to the door at the end of the level. There are three diamonds in the bottom-right of the level that you will have to use the fire button to collect - you can hold this button down and press a direction to collect an item in that direction without actually moving into the space (so in this case without being crushed by the boulders above).

This one takes a bit of care. You have to get rid of the boulders on the right while collecting the diamonds as they fall, then you go into the "mine" and collect everything in there. Be careful not to block the mine entrance, as this is also the exit back out to the door. Other than that you will just have to be careful not to get crushed or burnt, and to ensure that you do the level relatively quickly as time is often in the blue area at the end, so the two jelly beans are necessary.

This is a fairly easy level. There are two heart-shaped areas, and you must collect all the diamonds in the first area then teleport to the second area to collect all the remaining diamonds and get to the door. Be careful not to trap any diamonds and make sure you get the bottom-left and top-right areas on the first heart before you teleport. It may be a good idea to use the map when you're ready to teleport to check you've got everything!

The "incinerator" on this level is a row of fire onto which boulders and diamonds fall once the forcefield has been removed. You begin this level by collecting everything in the left-most compartment, teleporting through the next compartment and navigating the tricky right-hand side where you must collect all the diamonds, drop a boulder onto the monitor and escape! From here it's just a case of collecting the remaining diamonds and getting to the door in the centre - just make sure you don't get that final teleport...

This is certainly the most difficult level so far, but your reward for finishing it could be an extra life - the first one available in the game. You'll need to use the fire button to do the very first part of the level by pushing the boulders away one by one. Then you'll have to collect all the diamonds on the right - the difficult parts being not trapping one and ensuring that you can get back out to the teleport. The left-hand side is fairly straight forward as long as you can run from the falling boulders quickly enough.

Another tricky level - you'll have to use the gravity here to get to all the diamonds at the bottom of the level, and you'll have to get them all before it runs out or they'll be trapped. Then it's a case of removing the forcefield and collecting the diamonds on the right. A good tip here is to allow the two diamonds and a boulder on the far right to fall (rather than collecting the diamonds straight away) to allow you to escape the pit at the bottom.

Another level where the reversed gravity is essential to completing it. The first difficult part is the second chamber where gravity is reversed, but you'll need to leave a path through to the next teleport at the bottom (or at least a fire above the teleport so a bubble can be used to get rid of it). After that you'll have to navigate through a third chamber, then into the centre where judicious use of gravity and falling boulders needs to be used to hit the monitor and free the door. In here, use the bubbles to guide a boulder down on top of the monitor.

You'll have to be quick on this level - there's a long route from the start to the main part of the level on the right, and at the end you'll have to make your way all the way back to get to the door, so ensuring you don't block your way is essential. The fires in the bottom-right have to be removed one by one using the bubbles, and the boulders at the top need to be dropped onto fire to free the diamonds.

This is the first level that has wet hell soil (earth that responds to gravity), and it's a fairly simple one. The earth can't actually kill you if it lands on your head, so the only hazards are the boulders and diamonds, which can. A good tip is to do the level from top to bottom.

It's important to do everything while the gravity is reversed on this level (the second gravity is just to get to the door), the main thing being removing the forcefield by removing the earth above the boulder that is sitting on the monitor, so it rises and falls again. Be sure to remove all but one of the fires at the bottom of the level so you can collect the diamonds down there and escape again.

Honeycombs is a giant maze level where you start and end in almost the same place, so it's another case of ensuring that you allow yourself a path back as you're navigating the level. There's not much time and not much space - a number of the areas of this level will leave only a narrow path to get back. There is an extra life that can be gained fairly early on in this level, so if you can keep getting that you'll get as many tries as you like.

Care must be taken on this level not to trap anything when the forcefield is removed - and for this you'll have to remove the fire and boulders in the top-right first, one at a time. You'll also have to be careful not to become trapped when teleporting - the routes away from the destination teleports will need to be cleared first. Apart from that it's just a case of melting the many boulders on the fires at the bottom to free the diamonds and, as per usual, doing everything as quickly as possible.

This is the second level with wet hell soil, and like the first it's not too difficult. Things can get interesting as the wet hell soil responds to gravity, but you only actually need one of the gravity sticks to allow the fire above the monitor to fall back onto it. Then it's a case of collecting the previously-trapped diamonds and removing all the extra fires that have fallen back down. There are plenty of available bubbles to do this, however.

This is a difficult level where it's very easy to make a simple mistake that will mean you to have to start again. The first tricky part is hitting the monitor - you'll have to use the bubbles to guide an item down onto it (after removing the fire that is initially sat on top of it). From there you must quickly move down the long path of diamonds on the right (with the generous points per diamond value this is worth 1,000+ points), then get rid of the remaining boulders and fires to free up the rest of the diamonds. There are exactly enough bubbles and barely enough time to do this!

The Snare is a maze level that is without doubt the hardest level of the game so far. There is nothing particularly puzzling about what you have to do - other than doing things in the right order, getting through some tight gaps and ensuring you don't block your path back it isn't too bad. The problem is time. There are no jelly beans and you can't hang around for a second. Should you manage to complete the level, or even nearly complete it, an extra life will be yours.

No puzzles here, it's almost impossible to lose a life by getting crushed so once more you're against the clock. Which is a problem, because you can't see where you're going! The earth and the walls look exactly the same, aptly a question mark. The maze has been designed such that diamonds that appear to be close by (for example the one that starts two tiles below you) are actually miles away. Use of the map is absolutely crucial here - you'll have to take in as much information as you possibly can when it is shown.

This level isn't quite as hard as the previous two - the only thing you've really got to contend with here is a lot of boulders, so you'll just have to be careful not to get crushed or to trap any diamonds (and there are a lot of both boulders and diamonds). Take care when getting the leftmost two diamonds - you'll have to remove all the earth and use the fire button to collect them as they fall. And make sure you collect the path of diamonds on the right down to the door last, otherwise you'll almost certainly become trapped.

The main problem on this level is removing the forcefield. You cannot drop wet hell soil on the monitor, so you'll have to use a boulder instead, and the only way to get it through the central chamber is by repeatedly reversing gravity to allow it to move up and over the walls that are in the way. The teleports can be used to go inside the chamber to get behind the boulder to push it. Otherwise this level is simple enough, again just be careful not to trap anything. An extra life is available, but only after the monitor has been smashed.

This level starts before you do! Be sure to get the three diamonds in the longest line of boulders before they fall on the fire and get trapped. The monitor is sat on top of the door, so you'll need to drop a diamond rather than a boulder on it so as not to block your exit. Other than that just be prepared for melting a lot of boulders and getting through a number of tight spots.

This is an extremely difficult level. There is very little time available and plenty of ways to get yourself stuck so you have to start again. The bottom-right area must be done twice (once to remove the teleport and again to collect the diamonds) and on the left-hand side the fire must be removed to allow a clear passage to the diamonds at the bottom. There are a lot of tricky areas where it's difficult to predict how things will fall - especially since wet hell soil is thrown in as well.

This is another very tricky level. There's lots of removing fire required here, particularly the two "Great Walls" on the left and right. To do this you'll have to manoeuvre a number of bubbles through some tight spots, and there are exactly the right number so again one mistake can be fatal. Be very careful with the monitor - remember that whatever you drop on top of it will end up blocking the door. Time shouldn't be a problem on this one.

The idea of this level is to remove the teleports that are blocking your way one by one. Each time you do this you'll be taken back to a teleport at the top of the level, but remove one too many of them (don't get them all!) and you'll teleport to the top-right of the level, where you'll become trapped. This is a time-consuming level, but there are plenty of jelly beans, so you shouldn't run out. Be careful, particularly when the forcefield has been removed, not to trap anything - the boulders and wet hell soil do tend to get in the way on this one. There are plenty of points to be had though at 50 points per diamond, and there's an extra life available towards the end of the level.

This level is not too bad. The first part is not obvious as you must let the boulders above you fall to clear a path at the top, but must not trap any diamonds. After that you move to the right and do everything there, taking care not to block your path back. Then it's back round to the door and an extra life. There is a lot of running from falling boulders and ducking into gaps to be done here, but nothing too taxing.

This is a really nasty level that takes absolutely ages to finish; there is a lot of extra time available and you'll need it all. The main problem is getting the monitor. You'll have to stack up a column of boulders high enough such that one can be pushed across on top of the monitor, and the only way to do that is to line up a row of bubbles to push them, one step at a time, into the hole to the left of where you start. Unsurprisingly, there are exactly the right number of boulders and bubbles to achieve this! There is another extra life available, but only after you've removed the forcefield.

Be very careful on this one - with over 100 fires it's easy to get yourself inadvertently burnt. There are one or two bubbles around which you'll have to use wisely to smash the monitor before any teleporting is done. Once you've done that, you'll have to fetch the bubbles from the bottom chamber to get rid of more fire to get the remaining diamonds and free the door. This can be time-consuming, but there should be enough jelly beans available.

This is a very clever level where you must avoid smashing a monitor until the last second so as not to block the door. If that doesn't sound hard enough, the entire bottom row of the level consists only of monitors, so dropping one item down too early means failure. And if that doesn't sound hard enough, you can't tell the boulders and the earth apart! You'll have to learn the safe routes that allow you to collect diamonds without causing an avalanche, and, as with level 20, you'll have to take in as much information as you possibly can when viewing the map.

Over 45% of this level is covered in bubbles, so things can get a bit tight here. There is some fire which helps to get rid of some of them, but for the most part you'll have to plan your route so you don't trap any diamonds, which will be the main reason for failure on this one. The best way to do this is to try to pile up the bubbles where you know you won't need a route through, so as to clear space elsewhere.

This is it - the final level of the game and it is without question the most difficult. There are 20 jelly beans and you'll need every single one, meaning you'll spend three and a half times your originally-allocated time on this one. The idea is to get rid of the huge vertical wall of fire on the right in order to free the three diamonds stuck behind it. There are exactly the right number of bubbles available to do this situated in various positions around the level. Some of them are a long way from the fire, so you will have to spend a lot of time navigating a lot of bubbles through tight spots where one push in the wrong direction spells failure.

If you do manage to complete this level then congratulations - you have completed Earth Shaker!