Krogen on mapmaking
Open your favourite maps in the editor and take a close look at them. Analyze what you see. Why are things the way they are. As a beginner, don’t be afraid to copy certain patterns and techniques that worked elsewhere. This is wesnoth, no one will care for a little plagiarism.
When starting a new map, it’s best to make it the biggest possible, both Width and Height 200. You can resize it later, once you see just how much terrain will you need. This way you only have to do it once, and not in the middle of working on it, because you ran out of space. It’s practical to start building the map somewhere around the middle, for this same reason. That way you can focus on working entirely, the map can spread as much as it needs to in all directions, and you don’t have to worry about resizing constantly when something doesn’t turn out the way you first pictured it.
The new map should not be all grass. Choose a terrain type that is very easily distinguishable from the rest and preferably one that you don’t intend to use later, or very sparingly. Fill out the entire map with this one terrain. It can be for example Lava or Snow, if you don’t think your map will have any of those. Personally, I recommend the Ethereal Abyss/Chasm terrain type. It stands in contrast to nearly all the rest, and that’s most important when it comes to choosing here. It worked for me really well, and it’s been used by Horus before. Whatever you end up choosing, this will represent the tiles that you didn’t touch yet. The parts of the map that haven’t been made. This way you will very easily see the whole picture, what’s done, where you are at in the process, how much you did so far. If it’s all grass, it’s easy to get confused.
As a beginner mapmaker, your map should be symmetrical. There are asymmetrical maps, that are good, but making those is an extremely difficult task. I admit, I personally don’t think I’d be capable of making one that works, and is not terribly broken in one way or another. I’m only saying this from a gameplay perspective, naturally. If the terrain types don’t look alike, but function the same way, it’s perfectly alright to have different ones at opposite ends of the map, to achieve better aesthetics. If you are dead set on making an asymmetrical one, then your best chance is to make it completely symmetrical at first, and once you are done, then consider your options and edit it carefully.
When making a map, you should always build the middle section first and work your way out. The middle is the most important part of the map, and you can always adjust the edges to it. If you start with the edges, you will be very limited when it comes to the middle, in more than one way. Mostly you will not have a particular size in mind when you start the map, it will kind of just come to be as you are working. If it turns out to be a little bigger or smaller than you anticipated, and you have a middle section drawn, it won’t be much of a problem, as you can always adjust the edges. If you have the edges done first however, changing the size will be much more difficult. You will have to go back and waste a lot of time on stuff you’ve already done. So, start with the middle.
Now, what do I mean by “middle”? How much of the map’s terrain does that include? Well, it shouldn’t be small. Sometimes even half of the map, though usually not. Generally, as you work your way out from the inside, you should end up having roughly 1/3 of each of the respective side’s villages at the current edge, sometimes even more than that. Basically, most of the frontline villages. Then, you can claim that you are done with the “middle”. Try to be as faction-neutral as possible here. You can potentially have a water area here (like Weldyn Channel or Swamp of Dread) or unusual terrain types (snow on Sullas Ruins). Be careful with things like forests, mountains and hills. There will be a lot of maneuvering around these areas, what you place here will generally have much more of an impact than what is elsewhere.
Once you are done with middle, you should draw the starting keep, or keeps, if you intend to have a more complicated initial village grabbing. Based on the placement of the villages connected to the middle, you can count how far the keep can be, so the players can reach them in time, with a reasonable recruit pattern. This is when you place the rest of the villages and the path to them from the keep(s). There are maps with 6 villages per side, but that means lower number of units in the game, therefore more RNG involvement. 7 or 8 are good numbers, 9 or 10 are alright aswell. As a beginner, you should aim for these numbers. You also have to figure out at least one way for each faction to efficiently capture their villages in time, and then have a capable army. Admittedly, it’s more challenging for the mapmaker, but it’s better to provide options here for the players and have multiple legitimate ways to do the village grabbing. Competitive games start with Dawn, and first night pressure on the other side should be possible with a chaotic army, without being overwhelming. So generally, units with 5 movement points should be able to reach and threaten the opponent’s side by turn 5. You also need to place terrain around the frontline villages carefully, that help with defending them. But you can’t make it too easy to fortify them, or the attacker will have a crippling disadvantage. This balance is difficult to get right at first, and will probably require playtesting later and several changes to the map.
On most maps, normally all villages can be grabbed by turn 3, alternatively 4. What is really important, is that unless the mapmaker pays close attention, Player 1 can sometimes reach a village on the opposite side, before Player 2. This, combined with a rush for example can be fatal and a reason alone for the map to be unfit for competitive play. Also keep in mind that Gryphon Riders have 8 base movement points, 50% chance to get quick trait and very advantageous movement costs. Elvish Scouts have 9 mps and 40% to get quick, though their movements can be limited with terrain more easily. You, as the mapmaker have to prevent village steals by these units during the initial village grabbing. If you start to really hate these two units, you know that’s a sign that you are improving as a mapmaker.
When you have the middle, the keeps and all the villages, you should do the rest of the map. This is a good time to set the map to its final size. You should end up with a healthy number of forests, hills, mushrooms, mountains, water, swamp and castles (not always necessarily with keeps attached). There are some exceptions (Sullas Ruins doesn’t have any mushrooms, Hellhole doesn’t have mountains), but generally for a beginner it’s better to have all of these. There are also maps where water control is more important (Fallenstar Lake, Weldyn Channel) and other ones where it is nearly pointless (Den of Onis, The Freelands). While it’s for the best to always have some water on the map, it doesn’t necessarily cause imbalance if its importance takes a backseat. Alternatively, it can be more dominant too without having too much of it, which then gives the players an opportunity for more creative gameplay. This is mostly a question of theme and preference. Terrains like cave, ice or sand are not mandatory generally, but can be a nice addition if it fits the theme, or even for balance reasons, if you feel like a faction or certain units need to be weakened or supported.
It's important to read the Help occasionally, if you don’t have all of the unit stats memorized, to know what you need for a good terrain mix. Saurians for example can be quite dangerous to the balance of smaller maps. They are only really limited by snow, ice and water. Forests and mountains slow them down a little bit, but they still get 60% defense there. If you have a map with a theme where snow and ice doesn’t fit, you are only left with water to keep their movements in check, so you need to use it wisely. This is a really major problem on Den of Onis for example. It is small, has plenty of hills and cave, no ice and very little water. Therefore, saurians are completely overpowered on that map against Loyalists for example. But saurians are only one type of the units that you need to pay attention to.
If you want to deviate from the average, then you need to have a reason for it. Let’s look at Sullas Ruins, which is a well-known map and accepted by the competitive community. And yet, its lack of mushroom terrain makes it unique. Mushroom is important to balance a map for Undead gameplay. It is also the only the only tool other than cave that slows down gryphons. (Important too to slow down orcs, but right now that’s secondary.) The map is quite open though and relatively large, which means dwarves with 4 or 5 mps will be quite limited on it. On the other hand, gryphons will be more efficient than usual. So, the Knalgan Alliance overall comes out alright, the imbalance doesn’t go to an unacceptable level. There is plenty of deep water in key positions, that limits Undead far less than other factions, which helps them for the lack of mushroom. The middle of the map is also faction-neutral, due to snow. Castles, often without keep attached, appear frequently too, another element that mitigates the effect of a key terrain type missing, as it is pretty much the same to everyone. (Except for Drakes, but they already do well on this wide-open map.)
Now, having said that, no map has perfect balance. You can find issues with each and every one of them. That’s not an excuse not to strive for it though, on the contrary. Keep in mind that some of these flaws are quite minor and usually have little to no effect on gameplay.
As seen with Sullas Ruins, two or several unusual mapmaking methods can balance each other out, which might be broken in themselves. Deciding this usually requires testing, and outsider opinions are recommended. On maps where Player 1 would have a major advantage, sometimes it is a considerable option to not give Player 2 a preflagged village, but to give Player 1 a different starting location, that slows down the initial recruiting. A well-known example of this is Sablestone Delta, but I myself have personally done this on one of my own maps and it helped improving it greatly. (It was still a flawed map, but that’s a story for another day.) Sometimes, when villages are more spread out, and/or the map is bigger than average, it can also be considered to give the players more starting gold than 100. Arcanclave Citadel is an example of this, and so is Thousand Stings Garrison. And again, I’ve personally done this too, on another one of my maps, where it had a positive effect.
Beginner mapmakers often make maps that are way too large to play on competitively with Default/Ladder era factions. There are large plains of flat, enormous village distances, gryphons and horses roam around uncontested. This will cause factions with more mobile and powerful scouting units to dominate, and the map will be horribly imbalanced. Northerners will not be able to keep up with a Loyalist army, except for their Wolf Riders, but those cannot possibly stand and fight against Cavalry and Horsemen. Units with 5 or 6 move points need to be able to walk between their villages without too much problem, in 2 turns at most. Sometimes it is okay to have a little greater distance, but if it happens too often, that’s a good indicator that the map is oversized. Wesnoth was not balanced for maps of that size and style. They are alright for casual gameplay, but if you want your maps to be taken seriously by the competitive community, you have to accept these rules. The game’s balance is far from perfect, but any flaws it might have, are dwarfed by the sheer imbalance of oversized maps. Those are really on an entirely different level. Having a tiny gap on a boat’s side does not excuse a gigantic hole at its bottom.
Again, there are exceptions, but those are well-designed maps, with a lot of thought and care in them. Arcanclave Citadel is enormous in size for example, and has 13 villages per side. Yet, it is an acceptable map for competitive play and doesn’t have a clearly broken matchup. The gigantic keep makes it possible to reinforce either one of the three main frontlines instantly. The picture, that’s so common on oversized maps, where 5 mp units desperately try to chase down a scout that slipped behind their lines, rarely occurs. Even when it does, the keep makes it possible to catch up with it quickly with a well-placed new recruit. If you want a big map, you have to acknowledge these issues and do something about them. It needs to have some saving graces at the very least. If it doesn’t, then those who know the first thing about Wesnoth maps, can tell that there is a problem, just by taking a look at it. Only those who know the rules can afford to break them.