Marble Madness is an arcade video game designed by Mark Cerny, and published by Atari Games in 1984. It is a platform game in which the player must guide an onscreen marble through six courses, populated with obstacles and enemies, within a time limit. The player controls the marble by using a trackball. Marble Madness is known for using innovative game technologies. It was Atari's first to use the Atari System 1 hardware and to be programmed in the C programming language. The game was also one of the first to use true stereo sound; previous games used either monaural sound or simulated stereo. In designing the game, Cerny drew inspiration from miniature golf, racing games, and artwork by M. C. Escher. He aimed to create a game that offered a distinct experience with a unique control system. Cerny applied a minimalist approach in designing the appearance of the game's courses and enemies. Throughout development, he was frequently impeded by limitations in technology and had to forgo several design ideas. Upon its release, Marble Madness was commercially successful, becoming a profitable arcade game. Praise among critics focused on the game's difficulty, unique visual design, and stereo soundtrack. The game was ported to numerous platforms and inspired the development of other games. A sequel was developed and planned for release in 1991, but canceled when location testing showed the game could not succeed in competition with other titles.

Mendel Palace, originally released in Japan as Quinty (クインティ, Kuinti?), is a 1989 action/puzzle arcade game co-developed by Freak and KID. It was published in Japan by Namco and in North America by Hudson Soft. Mendel Palace was Game Freak's debut title, and the first game designed by Satoshi Tajiri.

Millipedes (class Diplopoda) are myriapodous arthropods that have two pairs of legs on most body segments. Each double-legged segment is a result of two single segments fused together as one (the name "Diplopoda" comes from the Greek words διπλοῦς (diplous), "double" and ποδός (podos), "foot"). Most millipedes have very elongated cylindrical or flattened bodies with more than 20 segments, while pill millipedes are shorter and can roll into a ball, like a pillbug. The name "millipede" is a compound word formed from the Latin roots mille ("thousand") and pes ("foot"). Despite their name, no known millipede has 1,000 legs, although the rare species Illacme plenipes has up to 750. Common species have between 36 and 400 legs. There are approximately 12,000 named species in ca. 140 families. The longest species is the giant African millipede (Archispirostreptus gigas). Most millipedes are slow-moving detritivores, eating decaying leaves and other dead plant matter. However, they can also be minor garden pests, especially in greenhouses where they can cause severe damage to emergent seedlings. Millipedes can be easily distinguished from the somewhat similar and related centipedes (Class Chilopoda) which move rapidly, are carnivorous, and have a single pair of legs for each body segment. The scientific study of millipedes is known as diplopodology, and a scientist who studies them is called a diplopodologist.