Thanks for playing. There were plans for some additional mechanics (pickups, more varied landscape, etc.) and additional enemies (elite vampire hunters, Van Helsing himself as a boss, etc.) that were cut to keep the scope small. There's no requirement in the jam that the game has more than one mechanic to fit the theme (indeed, the rules say that it's entirely optional), but not only is there a countdown in the imminent sunrise, but the pun in the game's title and concept.