Tajemství Oslího ostrova

• Publisher — Vochozka Trading • Programmer — Petr Vlček • Artist — Jarek Kolář • Platforms — PC • Released — 1994 • Genre — Adventure

Jarek Kolář and Petr Vlček began working on the game in 1992 using school computers in the gymnasium of Slovanské náměstí in Brno where they were students. They wanted to use their own game-making tools as well as the ZX Spectrum tools they had been working with. In 1993, Petr Vochozka sold the first-ever Czech commercial adventure game for the Amiga entitled Světák Bob. Later that year, he founded Polička-based Vochozka Trading and released Tajemství Oslího ostrova as the publisher's debut title.

Development took place between 1992 and 1994. In the first year, the developers used their school computer after receiving permission from their computer science teacher. They faced several challenges, as there was limited information on how to make video games available to developers. Visual assets from other adventure games were used, which, years later in 2018, caused the magazine Excalibur to express surprise that there were no licensing issues. However, the game's sound effects were created by the developers themselves using computer speakers. Tajemství Oslího ostrova was also one of the first Czech games to feature developed graphics.

Originally, Kolář and Vlček had no plans to make the game commercially available. They created it to prove that Czech citizens could create a game on par with international productions. They did not care if the game was released commercially or as freeware, but after seeing an advert by Vochozka in Excalibur, the only Czech game magazine at the time, they joined Vochozka under the Pterodon Software brand. The game sold 2,000 copies for 240 crowns each, a considerable increase on Světák Bob, which had sold only a few hundred copies. Vochozka set up an exclusive contract to spread the games of the Pterodon team. The retail version of the game was originally wrapped only in a plastic bag. A paper-box edition was not available until November of the same year, at which point the second Pterodon Software game was released entitled 7 dní a 7 nocí. The game was released only five years after the Velvet Revolution, when only a small fraction of Czech society understood English. By the end of 1996, Vochozka Trading had produced twelve games. An English fan translation was released in 2023.

The player takes control of the Guybrush Threepwood parody Gajbraš Trípvůd, who, after an unsuccessful pirate raid, is on the run from LeChuck parody LeGek.