Welcome to Tower And Dragon 3.0. Only 8K Required
For updates and new information, go to: Tower And Dragon.

3.0 has been released! Teaser Video (2 minutes)
For 3.0 Release Details, TAP HERE
For How To Setup, TAP HERE

The Making Of 1.0 (36 minutes)
Tower And Dragon is a classic dungeon crawling adventure with primary and offhand weapon, armor, quest storyline, moving walls, teleportation, and unique tilesets and monsters for each dungeon level. Your character starts out just after landing a boat on the shore near an ancient ruin, discovered by following a dream. The game is a tribute to the game that inspired me to become a programmer: "Dungeon" from 1979. Like Dungeon, this game only requires 8K of memory.
Tower And Dragon is written in assembly language, only requires an 8K Commodore PET, and is playable by disk drive or tape cassette on ROM1, ROM2, and ROM4 systems. You can play with more memory, but part of the design was to make sure the game would work on some of the oldest stock PET systems still around. Designing under these tight constraints was a monumental task where every byte counted.
The audio soundtrack on the splash screen uses Shiru's BuzzKick engine, converted to the PET and gives Tower And Dragon a unique and distinct audio that new games will follow. He also converted the theme music to run under BuzzKick. While the splash screen utilizes BuzzKick engine, it is not used in-game due to lack of memory. Therefore, only simple audio is utilized while in-game.
Lastly, to keep with the vintage theme, I recovered the data from maps in a game that I made as a boy in 1980. Those vintage maps are utilized for the ancient ruin in Tower And Dragon!
Norbert Landsteiner has a wonderful online PET emulator with recently released version 2.0 that includes audio. Play Online at Masswerk Emulator here: Masswerk: Tower And Dragon. This will make it easy for anyone to try out the game, as well as any other vintage programs for the PET. His powerful emulator correctly works with Back To The Pet, A Bright Shining Star, and Faulty Robots.
Player Quotes:
- Kimberly Cook- It was beautiful.
- Marshall Sutherland- The thought that this whole thing runs in 8K just boggles my mind.
- Richard Suematsu (ref. plot)- I like how you don't understand what's going on in the first 2 levels and then it starts to come into focus.
- Frederic Bezies- ...The end is really touching. For that alone, it rewards the fact of having invested 35 minutes per level to explore them completely, because the secret passages are rather numerous.

Additional Tips:
- Be Thorough. Search for secret doors by pressing E every 3 tiles (12 moves) or so. This will reveal any secret doors not veiled in dots.
- Saving can only occur when at the boat or on the stairs. When the game is restarted and load is performed, your weapon,
armor, treasure, and player's level is restored. However, the fog of war and monsters are reset. Thus, the ideal time to
save is when starting a new dungeon level.
Release 3.0 Notes
Over the course of several months, as a hobby I found ways to optimize code and memory in Tower And Dragon(T&D). At one point I had over 300 bytes of free memory. I had not seen over 300 bytes of free memory since prior to adding audio version 0.9 beta. Programing Version 3.0 could then begin.
While I recommend simply replaying, version 3 is compatible with the version 2 save files.
New:- Almost all monsters are animated.
- Armor and weapons have names.
- There is finally a use for gold. There is now a village with a vendor up north in the outdoor area.
- While there are a few other items available at the vendor, You can now purchase a heal enchant. The enchant activates once per purchase and is expensive. I didn't want to change the "feel" of the game too much. To heal you press H.
- There are a total of 3 new zones to explore in the game. I say zones as they are not ruin levels. The village is accessible from the outdoor area. The other two zones are accessible from the ruin.
- A few boss mobs have been added.
- If coming from version 2, The stairs down on level 1 are worth visiting.
- Level 3 has been mostly restored to about 85% (possibly more) to its original state as I made it as a boy 40 years ago. Not that it is an awesome area or anything, but still neat. If coming from V2: Going to the stairs down on this level is significant.
- There are better weapons available in the game than previously available. If coming from version 2, simply killing monsters on level 3 and 4 should upgrade.
- The end is much tougher if coming from v2. Let me know if you can beat it without any upgrades or leveling.
- Completely enclosing character's avatar in any stairs/boat tile temporarily changes your spawn point to that location until you change zones or reload.
- While there is only so much you can do with text graphics, the dragon animation is worth viewing.
- Added more help option on title screens.
- When you have won, be sure to check out what is cooking on the stove. I used almost all available memory on the level to add some polish.
- Rebalanced all the zones, painful. This required me exploring every room, and looting every gold on every level.
I can't tell you the number of times I had to clear every mob from the new zones to thoroughly test.
- A few Easter eggs have been added. Hint: A few things change based off of your progression.
- Support for quests has been added.
Technical
One critical goal that I have upheld is insurance that this game can be played easily from tape cassette. While the game is fun to play from disk drive and any PET system, tape cassette places some additional restrictions. If I removed the cassette restriction and playing only from disk drive, I could constantly load and unload code. Using this method, I could make T&D do anything and everything that a much later game like Secret of Mana does.
The reason I adhere to playing from tape cassette is the goal of this game is to allow play on a stock 2001-8 (8K) system with a tape cassette. This system was released prior to disk drives and most people never purchased a disk drive as it was too expensive and unnecessary since 8K programs load quickly from cassette.
This also means that the game plays fairly linear in order, as I don't want cassette players to constantly have to rewind and fast forward the tape cassette for non-linear progression. That said, you can go to the village to purchase upgrades. This requires a second cassette for the "village" so you can go there at any time.
Tape Buffer Reclaim
Tape buffer #1 (used for tape 1) has always been used for temporary variable storage and tape buffer #2 (used for tape 2) is used for ROM1 systems to patch the diskio so it actually works, allowing original systems to play T&D on a disk drive. However, Tape buffer #2 could be used if not on a ROM1 system and it could also be used if on a ROM1 system but playing from tape cassette. I could actually use the space for more permanent storage provided I used the opposite buffer from the tape cassette being used, so that is exactly what I did.
Code optimization
Between tape buffer memory reclaim and code optimization (more subroutines, finding small optimizations like jsr/rts to jmp, using yet even more bit operations), that placed me at over 300 bytes free. This occurred in late November and it was finally time to write some code.
During the entire process, I had to step away from it quite a bit due to tedium of no memory.
Programming
The first task was rewriting the animation code to use a simple form of compression. I then had to "rewire" the tile animations to use the new compression. I then painstakingly went through every level and animated about 90% of the creatures. Most have a combination of idle and an attack animation. I ran out of memory about 80% through this task and had to perform more code optimizations.
I had pretty lofty goals for this expansion. the original goals were as follows:- Animated monsters.
- Named weapons. While the names are boring as there is only 7 characters to display, it does make an impact on gameplay. This sounds simple but was a painful process as I had no bytes free at the time. Constant work to optimize. Once complete I realized that I had to name Armor as it looked funny.
- A shop to purchase upgrades and possibly a heal (very tall requirement!). I was hoping I could create a village and have the shop keeper there, but my backup plan was to have the shop keeper between zones as then the level map data is not necessary. While extremely painful, I was able to create the small village, keeping true to my original plan.
- Some form of heal.
- Play from tape cassette and disk drive.
- Not implemented: Ranged weapons such as a bow. Unfortunately, this did not make it into version 3.
- Not implemented: Confirmation before using save. This did not make it either. I could not spare the few bytes of code to put it in there.
A little math and silliness: I have over 500 blocks free on a standard diskette. Each cutscene and level takes an average of 10 blocks.... So in theory I could add possibly 50 more zones. I'm not going there, and it would get boring without ranged weapons and magic, but this does mean I could realistically add my entire D&D campaign into the game...
My daughter and I play this game with the toothpaste, and who it runs out on is the loser and must throw it away. Seeing it in the garbage by the other is admission of defeat. By the time we're done with the toothpaste, it looks like it is machine pressed. My wife related the toothpaste to my search for memory and I loved it! T&D is getting really close to machine pressed.
I currently have 2 bytes free. I do know of a few optimizations I could make to free maybe 30 or 40 bytes, but to implement anyting major like ranged weapons would take several hundred bytes. There is a possibility I could shrink each zone in order to have more space to code, but I currently did not want to break up the levels I designed as a boy.
I believe my major motivator for this expansion was strictly enjoyment of doing things in small space and doing something never done before. I hope you enjoy.

The Making Of 1.0(36 minutes)

Release 2.0 Video (3 minutes)

Release 1.0 Video (3 minutes)
IndieRetroNews Release Link: IndieRetroNews: Tower And Dragon
Disk Image:
dragonNN.d64 is the Commodore PET disk image. You can simply attach the d64 file as as disk drive on Commodore PET / Commodore Business Machine (CBM) emulators such as Vice.
Tower Folder:
With Commodore PET / CBM emulators like Vice and real hardware based SD storage solutions, there are benefits to mounting the tower folder as a virtual disk rather than using the d64. By mounting the folder as a virtual drive, you can then easily backup/transfer your character save file D.SAV.
In the emulator, once the proper virtual directory is mounted, to run the game:
BitFixer's PETdisk MAX 2.0 does not currently support write operations to a d64. Instead, copy the game files from the tower folder into the root of the SD or network device. You will then be able to save.
Cassette TowerAndDragonCassetteNN.wav & TowerAndDragonNN.tap:
Refer to tapeseconds.txt for seconds offsets for each file.
You may need to invert the wav and/or tap for it operate with your hardware.
If recording to tape, make sure to scroll tape through clear header first.
If playing from cassette, it is normal for the screen to be blank while loading, but it should take no longer than two and a half minutes to complete the load.
It is recommended to use a completely different tape cassette for outdoor/town since you will head back there often. This is included in TowerAndDragonCassetteTownNN.wav and TowerAndDragonTownNN.tap. This file contains outdoor, town, and then outdoor again so it is easy to enter/exit the town area.
Tapfiles:
TowerAndDragonNN.tap contains the entire set.
TowerAndDragonTownNN.tap contains outdoor, town, and then outdoor again so it is easy to enter/exit the town area.
Vice Character Transfer To New Version
- To transfer your save character, load the OLD file as usual, then load your character as usual.
- Click the little black icon next to 8, I think it will be the rightmost thing in the status bar below the pet emulator.
- Tap attach disk to drive #8, find the new file.
- Save your character.
- Quit the emulator. Don't terminate it, it may not save the file from cache.
- Now change your emulator to the new file, but don't delete the old version until try loading your character.
- Restart Vice, but now pointing at the new disk image.
Version History
- 2024-01-05 Version 3.0 Released
- Almost all monsters are animated.
- Armor and weapons have names.
- There is finally a use for gold. There is now a village with a vendor up north in the outdoor area.
- While there are a few other items available at the vendor, You can now purchase a heal enchant. The enchant activates once per purchase and is expensive. I didn't want to change the "feel" of the game too much. To heal you press H.
- There are a total of 3 new zones to explore in the game. I say zones as they are not ruin levels. The village is accessible from the outdoor area. The other two zones are accessible from the ruin.
- A few boss mobs have been added.
- If coming from version 2, The stairs down on level 1 are worth visiting.
- Level 3 has been mostly restored to about 85% (possibly more) to its original state as I made it as a boy 40 years ago. Not that it is an awesome area or anything, but still neat. If coming from V2: Going to the stairs down on this level is significant.
- There are better weapons available in the game than previously available. If coming from version 2, simply killing monsters on level 3 and 4 should upgrade.
- The end is much tougher if coming from v2. Let me know if you can beat it without any upgrades or leveling.
- Completely enclosing character's avatar in any stairs/boat tile temporarily changes your spawn point to that location until you change zones or reload.
- While there is only so much you can do with text graphics, the dragon animation is worth viewing.
- Added more help option on title screens.
- When you have won, be sure to check out what is cooking on the stove. I used almost all available memory on the level to add some polish.
- Rebalanced all the zones, painful. This required me exploring every room, and looting every gold on every level.
I can't tell you the number of times I had to clear every mob from the new zones to thoroughly test.
- A few Easter eggs have been added. Hint: A few things change based off of your progression.
- Support for quests has been added.
- 2023-09-10 Version 2.7 Released
- Additional 20% Improvement in performance.
- On CBM 80 Column Systems: Game now uses full 80 columns for main game display. Movement is a bit sluggish, but makes up for it in extra view range.
It should be compatible with 8032, 8096, 8296, and SuperPET, as well as N and SK variants.
If you have actual hardware, I'd love to hear from you that it works, hopefully with pictures. I've only been able to test using Vice.
Many thanks to Frederic Bezies for playtesting & brainstorming.
- Tape cassette version is fixed, it was missing critical files.
- Slightly modified Level 3 and end boss maps to preserve theme in 80 columns.
- Minor bug fixes.
- 2023-08-29 Version 2.5 Released
- Support for CBM 80 Column Systems: While game only uses 40 columns(centered), screen does not corrupt on 80 column CBMs such as the 8032 and SuperPET. (Upgraded in 2.7 to support full 80 columns)
- Minor bug fixes.
- 2023-07-23 Version 2.2(2.0) Released
- The game starts with an outdoor adventure!
- There are now animated tiles.
- All levels are fortified with room decorations.
- Game programmed around ROM 1 bugs with the Commodore PET disk drive (IEEE-488), allowing it to work with a disk drive! To get it operating, see project rom1diskmagic.
- 20% improvement in performance.
- As with 1.1, this all runs in only 8K of memory. To make something this complex has been an ongoing battle.
- Unfortunately, character save files from version 1.x are not compatible.
- Fixed screen corruption on save (only effected tape cassette version in some cases).
- 2023-03-13 Version 1.1 Released
- Added support for Super Nintendo Controller.
- Minor bug fixes.
- 2023-02-27 Version 1.0 Released
Feel free to contact me jason at insanerocketry.com