Some bubbles burst after some moments, but most of them remain until someone decides to have them removed. To burst a bubble, use the ctrl key together with the direction to the bubble. Bombs Bombs can be collected and then used on any empty fields. To drop a bomb hold the ctrl key down and select the desired direction of dropping it. But be careful to be far off when the bomb explodes.
Bombs are especially useful to remove obstacles, like brick walls and boulders.
In some levels you can collect a shield which makes you immortal for several seconds. The screen is devided into the playfield, the top display and the status display. You can resize the playfield at any time using the small numbered buttons in the left lower corner or the keys F1 to F6 . A bigger screen display means a better view of the level, but requires a more powerful hardware. For a Pentium with 166 MHz it is advisable to select a zooming of 5 or 6.