Game Overview by Mike Finkelstein
The lead up to the development of (what many call the) Metroidvania genre happened in fits and starts. The earliest days of gaming saw developers experiment with what was even possible in the genre. There was no way to predict that a genre started a game played on an oscilloscope, Tennis for Two, would eventually lead to a diversity of play styles found within a Billion dollar industry. When you research the various games released across the whole of gaming you can eventually find ways to draw lines from the likes of Adventure through to Castlevania: Symphony of the Night, but that's with the benefit of hindsight. When games were coming out in different regions, at different times, and influencing each other in unexpected ways, seeing connections can be a lot harder when you're living through the era.
One game that seems like an obvious precursor to the Metroidvania genre, but isn't well known here in the U.S., is Dragon Buster. This title started life as an arcade game, giving players a chance at platforming adventure with the mildest of RPG elements. On it's own it likely doesn't seem all that influential, but once you see the similarities between it and the exploration adventures that were to come, such as Zelda II: The Adventure of Link, and you learn that this game may have giving the Nintendo team some inspiration on their own design philosophy, the parallels become more obvious. This isn't a proto-Metroidvania; it's at least two or three steps further back from there. But it was a formative step that helped to grow the genre and show where it could go in the future.
In the game players take on the role of Clovis, a bodyguard to the kingdom's royal family. Training for years with a monk, who taught the young warrior how to fight, how to heal from wounds, how to be the best at his chosen vocation, Clovis is the one tapped to rescue the Princess when she's kidnapped by an evil dragon. Clovis has to explore the world, going from location to location, fighting through towers and dungeons and caverns, all to find the Princess, defeat the dragon, and save the day.
Dragon Buster is a side scrolling adventure. The player has to navigate through various 2D layouts, fighting through rooms of enemies and, at each turn, looking for the exit from the dungeon. Often this requires fighting some enemy guarding the right room to reveal the door and escape. Once a location is explored, Clovis gets to move on to the next location to continue the process all over again. It's a simple, but effective, was to construct an arcade adventure game.
As it's an arcade game, Clovis is given limited resources with which to start his journey. He has a basic health bar, a sword in hand, and the knowledge that he has to get from point A to point B. His health bar is persistent inside the dungeons, only filling up when he finds potions or gets to the exit (where he'll get a small refill before the next dungeon to explore). If he loses all his health that's game over and you'd either have to crank in another quarter or let the next player take over the machine.
With that said, Clovis can improve his stats over time. Certain monsters will drop bonus potions that will add health to Clovis's bar. This is a permanent upgrade, carrying over between dungeons, although the upgrades are only small improvements. These bonuses are also rare, with maybe only one to two in a full cycle of the game. But Clovis is also able to collect powerful fire spells that he can launch at the enemies, too. These are dropped by foes as well, meaning the player has plenty of incentives to fight enemies and gain these powerful bonuses.
However note that combat in the game isn't so easy. Showing the DNA that Zelda II would eventually inherit, this game arms Clovis with a dinky sword that he has to swing at all the enemies and pray he hits them before they hit him. He can stand and swing or kneel, and some enemies will use their shields to block the attacks unless they're aimed right. Some enemies will attack from above, others will crawl along the ground, and plenty of the boss-style enemies will throw projectiles at the hero. Learning how Clovis controls and what the timing is for his attacks is key to getting more than a few screens into the game.
The game is broken up into multiple zones, all linked via a branching path overworld. The player can choose what path to follow at given junctures, but this isn't a free-roaming overworld to explore. The dungeons, however, are nonlinear and can be freely explored until the player is ready to move on. Each overworld will have a small set of zones to explore, capped by the final dungeon where the Dragon resides. However, you won't save the Princess the first time you get to the end. You'll be sent back for a second cycle, then a third, and so on. It will take six passes along the overworld, with it growing more complex each time, before you can finally save the day and bring the true Princess home. Six cycles for a full loop, and then the game starts over for Clovis to do his adventure again (in true arcade fashion).
If you were to approach this game now it's likely it would feel a little crude and underdeveloped, even in comparison to games that would come out within a few short years. Zelda II, for example, takes many of the mechanics of this game -- the sword combat, the free-roaming dungeons, the horde of enemies -- and improves on the quality of the game play to make something far more interesting all around. With that said, this game is staggeringly good for 1984. It came out around the same time as Dragon Slayer and it's interesting to compare the two different styles these games took to the idea of exploration and stat management. Dragon Buster, in many ways, feels far more mature and developed, a complete concept executed very well for the time.
But its most important factor is how it influenced the nascent genre to come. Exploration, platforming, and combat all combined together in a single game? Many games to come would all borrow these ideas and use them, evolve them, and improve upon them. But Dragon Buster did it sooner, directly showing the way. You don't get to Zelda II or Vampire Killer or Castlevania II: Simon's Quest without Dragon Buster showing the way first. It's a formative title that, sadly, never saw release in the U.S. Even as fans in Japan received the game on multiple home consoles, and then Europe saw ports of the game as well, most of the West was left out. It's a formative title that, now, we have to go back and explore for ourselves. That alone makes the journey worthwhile at least once.
Similarities to Castlevania Games
Due to the way the game handles exploration and combat, the most direct parallel for the Castlevania series is certainly Vampire Killer. Due to the limitations of the MSX hardware, Konami had to make some changes to Castlevania when porting it to that hardware, so they put a greater emphasis on exploration, secrets, and collection. They ended up with a game that, in many ways, feels like an evolution of the formula Dragon Buster created, only let down by the weakness of the MSX hardware. Fighting enemies, collecting power-ups, and looking for the exit are all things the two games share in common, showing their collective DNA.
Of course, in style and sound Dragon Buster is a very different game. It's Medieval high fantasy instead of Castlevania's Gothic edge. But when it comes to game play, the two titles are very similar. And Vampire Killer was a clear marker for Konami's own exploration of the Metroidvania genre (as the genre was forming) making Dragon Buster one of the great granddaddies of the whole genre to come.