Making its debut in 1999, the Steel Eel is a custom roller coaster built by D. H. Morgan Manufacturing. At a height of 150 feet, Steel Eel is the tallest roller coaster at not only SeaWorld San Antonio, but at any Sea World park, along with Kraken at Seaworld Orlando in Florida. It was the second coaster built by SeaWorld, following The Great White (1997), after new management felt the park needed to offer more thrilling rides. Steel Eel had to be custom built to fit along the slim area beside the lake and utilizes a simple lapbar and seatbelt restraint system. Key elements of Steel Eel include two hills after the lift hill with a small valley between the two and a diving dogleg turn and triple humpback hills after its mid-course brake run. With a paint scheme consisting of bright yellow track and teal-green supports, it has become a permanent staple in the park's skyline. It is first Morgan coaster to deviate from a general cookiecutter design embodied by Cedar Fair for their three out and back hypercoasters: Wild Thing, Mamba, and Steel Force. Superman: El Ultimo Escape at Six Flags Mexico, built a couple seasons after Steel Eel, shares more design cues with Steel Eel than any other Morgan coaster.