20 frames per second, later recognizing this as "a major turning point in the creation of the game" and the point where he knew the polygon approach would work. He was able to take advantage of the Amiga's genlock capabilities to create rotoscoped animations with the polygons, using video recordings of himself performing various actions. Though he had tried to use smaller polygons (which Chahi called "pixigons") to construct the backgrounds for the scenes based on Deluxe Paint artwork, the process of creating them was excruciatingly slow, and he returned to using bitmapped images. While Chahi had a clear idea of how to implement his game engine, he mostly improvised when creating the actual content of the game, allowing the game to develop "layer by layer without knowing where it was going." He planned on creating a science fiction game that was similar to Karateka and Impossible Mission. Because he wanted to create a dramatic, cinematic experience, the game features no HUD or dialog, giving the player only a representation of the surrounding game world during both gameplay elements and the cutscenes progressing the story. However, with no idea of the technical limitations he would face while building out the story, he focused more on creating ambiance, rhythmic pacing, and narrative tension to the game. Chahi resorted to developing his own tool with a new programming language through GFA BASIC coupled with the game's engine in Devpac assembler, to control and animate the game, interpreted in real-time by the game engine, effectively creating his own animation sequencer. With the creation of the tools needed for building out the rest of the game by December 1989, Chahi began working on the introductory sequence as a means to validate the full capacities of his engine. The introduction sequence also gave Chahi the chance to explore the types of cinematics he could create through the engine. Chahi later considered this the "first step in the improvisation process" that he used throughout the rest of development. He finished the game's introduction sequence in early 1990 and started working on the first level. Chahi worked at the game at a linear pace, developing each section of the game in chronological order and influenced by his own personal feelings and attitude at the time. For example, as Chahi recognized he was trying to create a game on his own, the first portions of the game evoke