Kroz
| Industry | Video games |
|---|---|
| Founded | 1987 |
| Founder | Scott Miller |
| Defunct | 1999 |
| Fate | Discontinued Kroz series; later released as freeware and open source |
| Headquarters | United States |
| Products | Kroz series (Kingdom of Kroz, Caverns of Kroz, Dungeons of Kroz, Return to Kroz, Temple of Kroz, The Final Crusade of Kroz, The Lost Adventures of Kroz) |
| Website | 3drealms |
Kroz represents a collection of Roguelike video games developed by Scott Miller for IBM PC compatible systems. The initial installment, Kingdom of Kroz (1987), marked the inaugural release from Apogee Software and pioneered the business approach of providing the first episode at no cost while charging for subsequent parts—this model became a hallmark for Apogee and influenced numerous other MS-DOS shareware publishers.
The series was eventually discontinued in 1999. However, in March 2009, Apogee made the entire Kroz collection available as freeware and also released the source code under the GPL-2.0-or-later.
Gameplay
Players progress through various stages, confronting monsters with the ultimate goal of acquiring the Magical Amulet of Kroz. Throughout gameplay, players gather gems; each encounter with an enemy costs one gem but results in the monster’s defeat. The main offensive tool, whips, serve both to eliminate foes and break certain walls, though each whip can only be used once. Some levels feature procedurally generated layouts, requiring players to make swift tactical choices to optimize gem and whip usage—striking a balance between aggressive action and careful resource conservation to advance effectively.
Development
Drawing inspiration from the dungeon crawler Rogue, Scott Miller crafted Kroz to minimize randomness and highlight player skill rather than chance. The title itself is derived by reversing the spelling of Zork.
The original Kingdom of Kroz was programmed using Turbo Pascal 3.0, with subsequent entries developed in Turbo Pascal 5.0. These games operate in an 80×25 character text mode with 16 colors on IBM PC compatibles, utilizing ASCII and extended ASCII characters from code page 437 to visually depict characters, walls, monsters, and items.
Releases
Initially distributed under a shareware model, the series expanded to seven episodes where only the first was freely available while the others were sold commercially. The episodes include:
| Collection | Episode | Release | Levels | Notes |
|---|---|---|---|---|
| Original Kroz trilogy | #1 Kingdom of Kroz | 1987 | 25 |
|
| #2 Caverns of Kroz | 1988 | 40 |
| |
| #3 Dungeons of Kroz | 1989 | 30 |
| |
| Super Kroz Trilogy | #4 Return to Kroz | 1990 | 20 |
|
| #5 Temple of Kroz | 1990 | 20 | a.k.a. Valley of Kroz | |
| #6 The Final Crusade of Kroz | 1990 | 25 |
| |
| N/A | #7 The Lost Adventures of Kroz | 1990 | 75 | |
| N/A | #8 The Underground Empire of Kroz | Cancelled | N/A | Scheduled for release in March 1991. |
Both Caverns of Kroz and Dungeons of Kroz initially appeared in the disk magazine I.B.Magazette during 1987. Meanwhile, Kingdom of Kroz was submitted to the disk magazine Big Blue Disk in 1987 and published in 1988; additional titles followed there in 1989.
Aiming for wider exposure, Miller embraced the shareware distribution method by releasing a portion of the game free via bulletin board systems (BBS). To generate revenue, he innovated what became known as the "Apogee model," which involved providing one episode free while selling subsequent episodes through mail order directly to customers. This strategy was applied to the original trilogy by distributing only Kingdom of Kroz on BBS platforms and marketing the remaining episodes commercially through his company Apogee Software Productions. This approach yielded revenues estimated between $80,000 and $100,000, with daily earnings ranging from $100 to $500.
The title initially known as Castle of Kroz, later renamed Return to Kroz, was published in Big Blue Disk in 1990 before becoming the shareware episode for the second trilogy called the Super Kroz Trilogy.
In 1990, an upgraded version named Kingdom of Kroz II was introduced as the shareware episode encompassing the entire series. This edition included 21 new stages primarily sourced from later releases such as The Lost Adventures of Kroz. Consequently, distribution of the original shareware episode ceased; however, it remained available commercially as episode three while episodes two and three shifted forward one position in numbering. At this point, purchasing commercial episodes required prior registration through the shareware episode.
By 1991, enhanced "II" editions were launched for the remaining two episodes within the initial trilogy, replacing the original version of Kingdom of Kroz I.
Source code
At certain times, the source code for Kingdom of Kroz was sold at $190, while Return to Kroz fetched $350, and The Lost Adventures of Kroz commanded $950. Subsequently, prices shifted with Kingdom of Kroz II being offered at $400, Return to Kroz at $300, and The Lost Adventures of Kroz at $500. By 2009, the source code was made available under the GPL-2.0-or-later license.
Reception
Kingdom of Kroz originally earned first place in the game category during the CodeQuest '87 programming competition hosted by Big Blue Disk in 1988 and secured second place overall.
Legacy
Potomac Computer Systems replicated the Kroz concept along with its text-based format for the creation of the ZZT games, which utilized an identical shareware distribution model. This company eventually transformed into what is now known as Epic Games.