Hypersonic is another coaster that no longer exists, so we'll add it to the overrated coasters hall of fame. The "XLC" stood for "extreme launch coaster." Kings Dominion was raising expectations for the ride right in the name. The coaster accelerated from 0 to 80 mph in less than 2 seconds. But after HyperSonic's impressive compressed-air launch, which catapulted riders 165 feet straight up and down a top-hat tower, there wasn't much else to the experience. Like Kingda Ka, it was a one-trick pony--and an incredibly short ride to boot.