Pajitnov spent longer playtesting and adding to the game, completing it on June 6, 1984. This primitive version did not have levels or a scoring system, but Pajitnov knew he had a potentially great game, since he couldn't stop playing it at work. The game attracted the interest of coworkers like fellow programmer Dmitri Pevlovsky, who helped Pajitnov connect with Vadim Gerasimov, a 16-year-old intern at the Soviet Academy. Pajitnov wanted to make a color version of Tetris for the IBM Personal Computer, and enlisted the intern to help. Gerasimov created the PC version in less than three weeks, and with contributions from Pevlovsky, spent an additional month adding new features like scorekeeping and sound effects. The game, first available in the Soviet Union, appeared in the West in 1986. Pajitnov created a sequel to Tetris, entitled Welltris, which has the same principle, but in a three-dimensional environment where the player sees the playing area from above. Tetris was licensed and managed by Soviet company ELORG, which had a monopoly on the import and export of computer hardware and software in the Soviet Union, and advertised with the slogan "From Russia with Love" (on NES: "From Russia with Fun!"). Because he was employed by the Soviet government, Pajitnov did not receive royalties. Pajitnov, together with Vladimir Pokhilko, moved to the United States in 1991 and later, in 1996, founded The Tetris Company with Henk Rogers, which finally allowed him to collect royalties from his game. He helped design the puzzles in the Super NES versions of Yoshi's Cookie and designed the game Pandora's Box, which incorporates more traditional jigsaw-style puzzles. Pajitnov and Pokhilko founded the 3D software technology company AnimaTek, which developed the game / screensaver El-Fish. He was employed by Microsoft from October 1996 until 2005. While there, he worked on the Microsoft Entertainment Pack: The Puzzle Collection, MSN Mind Aerobics and MSN Games groups. Pajitnov's new, enhanced version of Hexic, Hexic HD, was included with every new Xbox 360 Premium package. In August 2005, WildSnake Software announced that Pajitnov would be collaborating with them to release a new line of puzzle games. Personal life Pajitnov moved to the United States in 1991, was naturalized as a U.S. citizen and now resides in Clyde Hill, Washington. He has a wife, Nina, with whom he had two sons named Peter and Dmitri. Dmitri died in a skiing accident on Mount