Mastiff is a publisher of video games on all platforms. Founded in 2002 with headquarters in San Francisco and Tokyo, the company has released titles in virtually every genre – including action, adventure, RPG, FPS, party, horror, and music.

Mastiff prides itself on KindnessQuality, and Fun. With these core values at the foundation of each decision and action, Mastiff achieves and delivers excellence. 

Meet The Team


Bill Swartz


Bill’s 35-year adventure in the video game business includes serving as a producer with Koei in Yokohama and then launching Koei America, serving as a senior VP at Activision, leading Activision Japan, and founding Mastiff. Nothing makes him happier than captivating and delighting players.



Mika Hayashi


Mika manages game development and Mastiff’s Japan office. Her motto: Always Forward. Always smile. She resides in Tokyo with her husband and their long-haired dog. She enjoys walking with dogs, skiing, playing wadaiko (Japanese drum), eating, and working at Mastiff! Recently, Mika started playing piano. And while she’s still leaning, she states that “it’s a great feeling when I hit a few right notes.” 😉




If Mastiff were an RPG, Brian would be both the shopkeeper and part-time wizard. Brian handles Mastiff’s finances, accounting, and administrative matters.

When he’s not crunching and slaying numbers, he enjoys spending quality time with his wife and three kids. He’s also quite the sports buff interested in college football and Premier League soccer. His favorite team is Chelsea. Watch out all you Manchester and Liverpool fans!




Born and raised in the Noto Peninsula, facing the beautiful Sea of Japan, Yasuo is a nature loving Japanese “ojisan” (an old guy). When he’s unable to revisit the beautiful beaches of his hometown, he enjoys singing bossa nova and playing the guitar. This multi-talented ojisan has been in the game industry for 35 years and has even composed music for a few games too.



Dylan Strehle

Marketing Lead

A video gamer, board gamer, CCG player, and tabletop RPG game master, Dylan is a self-described “Jack-of-all-Trades.” Got something that needs doing? If it’s related to social media, supports a marketing function, or pertains to any of his hobbies listed above, Dylan’s your man.


Ron Kurtz

Chief Revenue Officer

Ron is Mastiff’s wheeler-dealer road warrior business development, relationship, and sales guy. With more than 35 years in the industry, the last 16 heading sales for Square Enix, Ron knows everyone and has worked with some of the biggest licenses and titles out there.

When not making deals, Ron loves long, challenging bike rides and spending time with his twin daughters and wife.

AVATARS BY @mikeyturvey

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We’re always open to reviewing submissions. You have put a lot of work into your project and we understand that it’s something very special to you and all those involved. We promise to do our very best in responding to each submission and will ensure you that all submissions are treated with equal importance.