Koichi Ishii is a video game designer and the CEO and president of Grezzo. He is mostly notorious for his work on the Final Fantasy and Mana series at Square.
Ishii originally joined Square in 1987, where he worked as a designer for the first three Final Fantasy titles on Famicom; he is known to have designed the recurring Chocobo and Moogle characters that have appeared on the series ever since. Afterwards, Ishii was offered to work on a spin-off to the series, which led to Final Fantasy Adventure, a title which would inaugurate the Mana series, followed by Secret of Mana, Trials of Mana, and further titles.
In April 2007, he left Square Enix to form his own company Grezzo. The company has worked ever since with Nintendo on several Zelda remakes, as well as some original titles like Line Attack Heroes and Ever Oasis, under Ishii's direction.