Arcade game:Defender Stargate

Defender Stargate is the sequel to the 1980 arcade classic Defender. Eugene Jarvis- the designer of Defender- and Larry DeMar designed the sequel under Vid Kidz- the design company they started after the success of Defender. Released by Williams Electronics in 1981, the game was a success with about 27,000 units produced.
The objective of Defender Stargate is the same as its predecessor; defeat the enemy aliens while protecting the humanoids on the planet's surface. New controls and a larger variety of enemy aliens made Defender Stargate even more difficult than the original. Buttons for hyperspace, inviso, and smart bomb were all incorporated in the complex strategies that players devised for the game. An orange rectangular object in the middle of the playing field is the "Stargate" in which players can warp to another section of the play field or another level by entering it. Some names of the new enemies are the names of industry competitors spelled backwards: the Irata (Atari) and the Yllabians (Bally).
Defender Stargate was ported to many home units under the name Defender II. Although the arcade version is never referred to as Defender II, "Defender" is often dropped from the game's full title. "Stargate" is the prominent title found on the arcade game cabinet. The Defender series was continued with the 1982 follow-up, Robotron: 2084. The challenging gameplay of Defender Stargate captivated hardcore gamers and made the game a success.