

             For those who like a piece of history ...

      The caves appearing in the game are exactly those which
   were written in 1984 - 1986 for eight-bit computers. The word
   "exactly" means "one hundred per cent, if not stated otherwise".
   A few words may be lost, still.

      Boulder Dash appeared on the market in 1984 for Commodore
   and Atari, a year later for Amstrad and Spectrum. It was sold
   by First Star Software and Mirrorsoft, the authors were Peter
   Liepa and Chris Gray (Grey was the spelling in Commodore).
   Here it stands as Game 1, of course. It occupied no 1 in Top
   Ten list for unbelievable 14 months.

      The data part of the first Boulder Dash game was extremely
   easy to find, understand and modify. After the big success of
   the first release of the game, Stefan Strand and Chris Gray
   supplied new caves and new design of pieces, which were added
   to the unmodified code of the first game. It was again distributed
   by First Star Software under the name Boulder Dash III. In the
   meantime, Peter Liepa solely wrote Boulder Dash II, with a new
   code and different data storage, and added also two new pieces:
   expanding walls and slime. Boulder Dash II was a property of
   First Star Software, too, but only Commodore and Atari versions
   existed. It was never converted to machines based on Z80 processor.
   I followed the numeration, here they are as Game 2 and Game 3.
   The introductory screen with a blinking and tapping Rockford
   as well as the background music is borrowed from Boulder Dash II.
   Cave A, level 5 and Cave I, levels 4 and 5 in Boulder Dash III,
   were unsolvable because of the unremovable block of boulders,
   it is rectified here.

      A guy nicknamed Dr. Watson was smart enough to pick up and make
   use of any particular inaccuracy of Bouder Dash I and filled its
   data field by never expected numbers. His version was called Boulder
   Dash IV (here Game 4) and contains amoeba ready to turn into diamonds
   even if unbounded, dozen of Rockfords in one cave, steel wall which
   can be broken... It was a headache for me to design an algorithm so
   that all these irregularities were faithfully reproduced. The caves
   designed so could not be transferred to Amstrad and Spectrum, since
   there the algorithm was more precisely coded.

      Then, two groups of people, Zombie Crackers and No One, designed
   a lot of caves, again on the code of Boulder Dash I. Games by Zombie
   Crackers appeared with the name of Don Pedro, one member of the
   group, as Boulder Dash V, VI, ..., XI in 1986. Here they stand as
   Game 5, 6, ..., 11. I made a change in Cave J, Game 10: added fifth
   firefly. I deeply believe that with four fireflies only, the cave
   cannot be solved.

      Game 12 was formerly unnamed, it was a part of a Boulder Dash
   construction kit for Commodore, signed by Zombie Crackers.

      There are also compilations of a dozen or so games on one
   diskette for Commodore, signed by Replica Copy Crew or by No One.
   They contain games by Don Pedro mentioned before, but sometimes
   significantly modified. I included Game VIII as a Game 8A, because
   here, the changes really mean a different strategy, and the number
   of different caves is big.

      Games 14 to 25 are No One's games Boulder Dash 1 to 12, in
   this order. I added the eighth diamond to cave E in No One's
   Boulder Dash 2 (here Game 15) to allow to go through the cave
   also at Level 5.

      I have no idea about the authors of the last two games, Game
   26 and 27. Game 26 is taken from the Replica Copy Crew compilation,
   there it stands as Game J and called Boulder Head. I added exit to
   cave I. It was rather frustrating to pass through this hard cave
   and discover that no exit exists at all. Game 27 is the Brutalo
   Boulder Dash for Commodore. Its entry screen says only: "SUB7
   presents" and that is all what one can learn about the authors.

      I will thankfully appreciate any information revealing the
   identity of authors of all the games more sharply.

      While I said that the patterns of caves are 100% exact, the same
   cannot be said about pieces, colors and sounds. There were no "genuine"
   or "original" colors and sounds in Boulder Dash. They varied from
   machine to machine depending on its hardware capabilities, and that
   in turn influenced even the shape of pieces. What you can see and hear
   here is just some kind of a rough mixture of Commodore and Amstrad
   versions, and colors are chosen quite independently of the past. Forgive
   me, please. It was impossible to consider seriously 4bit graphics and
   3channel sound with the contemporary equipment.

      When in the choice of a cave, you will find another difference
   from the original: You can select any cave you wish, not only caves
   A,E,I and M. It was requested by too many people, who wrote me after
   having played my previous Boulder Dash remake. At levels 2-5, the
   original stepping is preserved.

                        Sincerely Yours
                                                      Petr Simon.
   December, 2000.
