Before Super Smash Bros. contained Nintendo characters, what was it known as internally?

The answer is not Dragon King: The Fighting Game. Super Smash Bros. was internally known as Dragon King: The Fighting Game only during its early development stages. However, the game went through significant changes and eventually transformed into the crossover fighting game we know as Super Smash Bros., featuring characters from various Nintendo franchises. The final name change occurred during its development process, making Dragon King: The Fighting Game an outdated internal title.