What a horrible night to have a curse, indeed.
October has come and gone. Usually, in the weeks leading up to Halloween, I play some Castlevania games on my various emulators (PC, phone, TV box, or handheld). This year, I was too busy to play much. I did play a bit of the PS1 Castlevania Chronicles on my handheld emulator, but not much. And yes, I know the new Castlevania: Belmont's Curse is out on Steam. I did consider buying it on release, but again, I was too busy to play it. I've heard good things about it (like, people saying it's hard -- bring it on!). I'll try to get around to it this winter.
Along with playing CV games, I'm always considering how to make a Castlevania style megadungeon for D&D in October. This goes back 20 years or so. I've got the old document from my first aborted attempt saved on my computer still. Back in my 3E days (shudder). That was focused on building the "Transylvania" around the castle, with the goal of making the central Demon Castle Dracula the megadungeon that required multiple expeditions inside, and to smaller dungeons outside, to complete and face Dracula up in his turret throne room.
These days, obviously, I'd use a much simpler system, like my own Treasures, Serpents, & Ruins rules. Or maybe adapt Missions & Mayhem. A CV style campaign module might be fun. Something a bit more historical than Hellspawn & Horror. Or maybe just H&H, minus the machineguns, smartphones, and sports cars.
Regardless of the rules system I use, the big problem, as other bloggers, DungeonTubers, and forum posters have pointed out in the past, is that the types of "locks" and "keys" found in exploration platformers like Metroid and certain Castlevania games, and similar modern games like Hollow Knight, are all things that work to limit progress in a side-scrolling video game, but don't work well in a game of the imagination, where players can try to do things that coding just doesn't allow in a computer game.
However, I think the Metroidvania style can work in a megadungeon. One just needs to think of the game system being used, and base the "locks" and "keys" around those game mechanics. Computer games usually do it by giving the player new ways to move. Double-jumps. Super jumps. Turning into a bat and flying. Running really fast that you break through walls. New weapons. Or sometimes, just messing around until you find a wall that will break or the right spot to perform some action that reveals a secret.
In a tabletop RPG, we have several options, some more metagame-y, some more diegetic.
- Character Level: Obviously, this has been the yardstick of D&D since the beginning. You don't need to be locked out of these areas, but once you get into them, it should be obvious if you're over your head, or you've entered an area way too easy, and therefor low reward. But having doors, portals, or whatever that can only be accessed once PCs hit a certain level is one way to lock off areas.
- Physical Barriers: These are hard to control. A Thief has their climbing ability. Levitation or flying magic isn't that hard to come across. A clever party, with time and resources on their side, could physically move or remove barriers through hard labor (build a bridge, tear down a wall, etc.). Still, this could be useful. Not every group will have the tools or desire to get past a barrier right away. MV games usually "key" these with new movement power-ups, but smart play or movement powers can be used in an RPG.
- Secret Doors: Again, there from the beginning. Also, very much part of the Metroidvania experience. If players find the secret door, they get access. If they don't, they don't. And you can put maps or hints or wands of secret door detection deeper in the dungeon to make them circle back to find any secret doors they missed. Very much in the spirit of the MV style game.
- Spell Requirements: At low levels, wizard lock can block access to areas, until the party gets a knock spell. Other low level spells, like bless, detect magic, read magic, read languages, or even magic missile (I magic missile...the darkness!) could be keys to unlock access to areas. Mid- to high level spells could do even more. Obviously spells like water breathing, passwall, dimension door, and teleport allow this. But there could be other situations where progress isn't possible without a certain spell at hand. And while this has overlap with level requirements, scrolls, potions, or other items may allow earlier access to some of these.
- Magic Item Requirements: This one is maybe the most MV. Beat a "boss" and get a magic item. Go back somewhere where you know there's something or somewhere you couldn't get to before, and use that magic item to access it. Of course, this has overlap with physical barriers and spell requirements.
- NPC Interactions: Many computer games use NPCs to give the player hints, clues, or the special means to access restricted areas. This is easy to do in RPGs as well, although the interactions will be more fluid and dynamic. And you've always got the risk of players killing or abandoning the NPC before they can deliver the information.
The important thing, in my opinion, is to design the megadungeon with gated areas, but don't prescribe any one particular key to enter that gated area. Sure, there may be a "preferred" method, but allowing for player creativity in problem solving is the greatest strength of the TTRPG over any other game. Cutting that out leads to railroading or inverse quantum ogres (no matter what the players do, they CAN'T get past the door).
In designing a Metroidvania style dungeon for a TTRPG, one needs to: divide the dungeon into sections, which are of different levels. Put secret rooms, passages, and so on in liberally. Have ways to observe, learn about, or otherwise detect the presence of areas within a section that can't be accessed directly. Make some connections between sections easy to navigate, others hard. Deliberately leave information, useful objects, or access to spells that will allow players to get into these secret or blocked of areas deeper in the dungeon. Also, make sure there is ample treasure all through the dungeon, so players can actually level up as they explore.
And most of all, when running the dungeon, allow players to get creative and bypass the "correct" keys to the blocked of areas. If you thought they should use fly to get to a region, but they use a combination of thief climbing and a potion of gaseous form, let them. If they hire a dwarven engineering team to tear down the giant stone slab door that's too heavy to open (even though you'd put a potion of giant strength nearby for them to find and open it with), let them. Also, keep the information flowing. As an individual, I may spend a lot of time trying to figure out a puzzle in a solo computer game. But my group won't want to wait for me forever in a TTRPG. The hints and information need to be available, so that the deeper you go, the more you learn about the areas you've already explored.
However, leave the players with the consequences of their actions. If they manage to find a clever way into a 4th level section of the dungeon while they're still only 1st, they will realize the monsters are too tough pretty quickly and if they're smart, retreat and return later when they're more powerful. Or maybe they'll get lucky, and manage to snag the magic item there that makes another gate trivial. Good! They're playing the game smartly and well if they do.
Computer game programmers can get away with making a wall that can only be blown up with the super-bomb, or a gate that can only be passed in mist form. TTRPG designers need to pose the challenges, and provide some keys, but be willing to let players find their own keys to get past the gates.
















