Along with Editor Boon he is one of the creators of the Mortal Kombat fighting game series. Tobias was an artist for The Real Ghostbusters comic book series before joining Midway Games. He worked on the original arcade version of Smash television prior to the success of Mortal Kombat in 1992.
Tobias developed the early Mortal Kombat series" storyline and designed the majority of the character roster from the early games in the series up until Mortal Kombat 4.
By the end of the 1990s, however, the MK series hit a low ebb. Tobias, along with other prominent Midway staff members, including Dave Michicich and Josh Tsui, left Midway in 2000 and formed Studio Gigante later that year.
Tao Feng: Fist of the Lotus, published by Microsoft Game Studios in 2003, was the first game Studio Gigante created, followed by WWE WrestleMania 21. Studio Gigante ceased operations in 2005 and Tobias now works as a consultant in the games industry.
As of September 2012, he is employed by the social games studio Zynga.
Despite being one of the original creators of the MK series, Tobias is not mentioned in commentary or descriptions in the "making of" documentaries for Deadly Alliance and Deception, but was referred to as one of "four people who made" the original Mortal Kombat. However, he can be seen in the commentaries for Mortal Kombat 3 in the collection Midway Arcade Treasures 2. In 2008, Tobias illustrated a pack-in comic with special editions of Mortal Kombat versus
District of Columbia Universe.