Netherworld

The object is to fly a small spacecraft and collect the required number of diamonds in each level. Once enough diamonds are collected, the craft must reach a teleporter to go to the next level before the time runs out. Aside from the time limit, there are various obstacles, ranging from monsters to items which can damage the craft or block the path. The ship can destroy some obstacles by shooting, sometimes turning them to diamonds as well. The game cover art features Tapanimäki's face. The cover art was done without his knowledge and approval. There was friction between the original cover artist and Tapanimäki; Unbeknownst to him, this led to the art getting shelved and new version was made. Tapanimäki did not see the final version until the press conference in London where the game was released, giving him a big shock. Many game magazines published a cheat code that only works in a work-in-progress version; this, along with some published POKEs, indicated that the game was leaked to pirates some six months before the release.