Game designer Toshimichi Mori announced over the weekend that he's left developer Arc System Works. Mori had been working at the developer for 19 years, and was a key creative force in its BlazBlue fighting game series. 

"I have nothing but gratitude towards the staff of Arc System Works and others who have worked with me, as well as all the users who supported us," wrote Mori on Twitter (run through Google Translate). "Thank you from the bottom of my heart."

Mori first became involved with Arc System Works as the developer of external company PicPac, which was helping with 2000's Guilty Gear X. He would join the developer officially in 2003, and later served as the director of the Guilty Gear spinoff BlazBlue: Calamity Trigger in 2008. 

BlazBlue would go on to become its own popular franchise, with Arc System Works alternating between developing games for it and Guilty Gear every few years. Mori typically served as a producer or director on future games in the series, including the 2018 spinoff BlazBlue: CrossTag Battle. 

Said Mori of his time at Arc System Works: "I cherish many of the experiences I have had during my 20 years there, whether it was working for various fighting game titles, developing my own title BlazBlue, or connecting with many of our users." 

"At the moment I’m thinking of creating and delivering a game for the users in some way, and am going to focus my strength on that endeavor. Your support would be much appreciated."