Complex sentence: Established as the Tennessee Valley Vipers and a charter member of af2, the Raptors migrated from the af2 (known as the Vipers in af2) to the United Indoor Football (UIF) after the 2004 season.
Split into simpler sentences: Established as the Tennessee Valley Vipers and a charter member of af2. The Raptors migrated from the af2 (known as the Vipers in af2) to the United Indoor Football (UIF) after the 2004 season.