Complex sentence: In the late 1980s, Smedman began to write for "Dragon" magazine, which led to her writing her first gaming adventure for TSR, Inc.--the creators of "Dungeons & Dragons"--in 1993.
Split into simpler sentences: In the late 1980s, Smedman began to write for "Dragon" magazine. This enabled her to write her first gaming adventure for TSR, Inc.--the creators of "Dungeons & Dragons"--in 1993.