Complex sentence: In 1991, Garcia was a founder of Microsoft Game Studios, where he completed the acquisition of subLOGIC (the developer of "Microsoft Flight Simulator") and was part of the DreamWorks Interactive joint venture.
Split into simpler sentences: In 1991, Garcia was a founder of Microsoft Game Studios. He also successfully completed the acquisition of the developer of "Microsoft Flight Simulator", subLOGIC, and was an integral part of the Dreamworks Joint Venture.