Steeplechase © 1975 Atari.
Steeplechase is a horse racing game. Up to six players can play against each other. You have to make your horse jump over obstacles on a horizontal course. The monitor has six rows for each horse, each with an individual color overlay. You always play against a computer player with horse number 7. The fastest horse wins.
Released in October 1975, selling at an MSRP of $1095.
The project name for Steeplechase was 'Astroturf'. The name 'Astroturf' is even still on the board. It is an early Atari board without any dedicated CPU (the computer was a TTL state machine), but had two graphics PROMs for the horses.
Atari 2600 (1981)