Within the Super Robot Wars (スーパーロボット大戦 Sūpā Robotto Taisen) franchise of tactical role-playing video games is Super Robot Wars Alpha (スーパーロボット大戦α Sūpā Robotto Taisen Arufa).
As with the rest of the franchise these were produced by Banpresto, which is now a Japanese division of Namco Bandai. The main feature of the franchise is having a story that crosses over several popular mecha anime, manga and video games, allowing characters and mecha from different titles to team up or battle one another.
The 'Alpha' series consists of Alpha, Alpha Gaiden, Alpha 2 and Alpha 3 games (in that order). "Part One" of Masō Kishin - The Lord Of Elemental also provides relevant information, taking place before Alpha.
Source: Wikipedia, "Super Robot Wars", available under the CC-BY-SA License.