The basic goal is, of course, to collect enough diamonds to activate the exit, and to get out alive (without being killed by various means or running out of time).

If he cannot solve the cave he must push the button ,

Hufeek
Hufeek is the player, and so Hufeek's movements are controlled by the player. It can move up, down, left and right only, not diagonally. The Control key (or Shift or space) can be used to "move without moving"; that is, everything happens as if Hufeek did move in the indicated direction, but Hufeek isn't actually moved. This is critical for some caves which require this technique. If something (gem or boulder) hit Hufeek, Hufeek explodes. Then there are 9 free places on its place.

MultiHufeek
There can be more Hufeeks in some caves. I named this "MultiHufeek". The player control only one Hufeek but he can switch to another one by pressing TAB key or number on numeric keybord. There could be max. 9 Hufeeks in every cave. This element is first used in Hufeek, no other Boulder Dash clone support this.

Dirt
Only Hufeek can move through dirt. Other creatures (except amoeba) can't. Boulders and gems don't fall through it, they sit on dirt without rolling off.

Boulder
The boulder, like the gem, is an object which falls down (what a surprise) and rolls off some other objects. If it can roll left as well as right, it will roll left. Hufeek can push it, if there is a space behind it. If a falling boulder hits a creature (firefly, butterfly, fly or Hufeek), then that creature explodes. The boulder itself does not explode.

Gem
You must collect these yellow gems. If you have collected needed number, the exit will open. Otherwise, the gem is almost identical to the boulder. Drahokam padá, stejně jako kámen.

Brick wall
Basically, brick wall is ordinary wall. Boulders or gems can roll off it and (unlike steel wall) it can be destroyed in an explosion.

Steel wall
Steel wall is better than brick wall. It remains unaffected by explosions. Boulders and gems sit on top without rolling off.

Exit
Exit looks the same as brick wall until it is open. Then it's blinking. Unlike a steel wall it can be destroyed in an explosion. 

Magic wall
Magic wall starts life dormant and visually looks just like ordinary brick wall, until a boulder or diamond falls on it. Then all magic wall in the cave gets turned on for explicit time and in this time any boulder or gem that hits the wall gets changed into a gem or boulder respectively and falls through. If there is any object underneath the wall at the point where the boulder or gem falls through, the boulder or gem is lost (which is sometimes a helpful way of getting rid of excess boulders). After a certain time has elapsed (the magic wall milling time), the magic wall expires; it goes back to looking like ordinary brick wall and any boulder or gem that fall on the wall just disappear. Boulders and gems do not roll off magic wall like they do brick wall.

Expanding wall
Expanding wall looks identical to brick wall, but boulders and gems don't roll off it. It grows sideways (left/right or up/down) through space whenever possible.

Firefly
Fireflies, like butterflies, are creatures which move around in a set pattern. Fireflies always like to turn to their left if possible (going round and round in circles if possible). If impacted, or on contact with amoeba or Hufeek, fireflies explode into space.

Butterfly
Butterflies, like firerflies, are creatures which move around in a set pattern. Butterflies always like to turn to their right if possible (going round and round in circles if possible). If impacted, or on contact with amoeba or Hufeek, butterflies explode into gems.

Fly
Third insect. Flies moves by another system than firefly or butterfly. Butterflies always like to move forward if possible. If not posible to move there, it turns to random direction. If impacted, or on contact with amoeba or Hufeek, butterflies explode into boulders.

Amoeba
This creature is stuff that grows randomly. If trapped such that it can't grow any more, it suffocates and turns into gems. If it grows too large, it turns into boulders - it will happen when it fill cca 22,7% of all cave fields. Fireflies, butterflies and flies will explode on contact with amoeba.

Slime
Gems and boulders can randomly fall through slime. The probability, that it let something to fall through can is set by "slime permeability", which can be in every cave different. Slime can be destroyed in explosion.

Box
Hufeek can move boxes everywhere by pushing. Box can be "overpushed" - it happens when Hufeek push box to the wall (or something else) and it means that they change their positions. Boulders or gems can roll off it.

  Locks and keys New in version 1.1.
Locks are objects like brick wall. If Hufeek collect the gem with their color, they turn into another object. Red locks turn into boulders, green locks turn into boxes and blue locks turns into free space.