Terrain is most of the work on a map, and most of the difference between a map that reads well and one that does not. The difference is usually a habit rather than a technique. Four traps come up again and again.
First, mistaking the canvas size for the budget. A 256x256 map is a container, not a target footprint. A map reads by how much is packed into it, not how much it covers - a layout with large, far-apart rooms looks like less work than one with small, crowded rooms, even though it covers more tiles. The instinct to “use the space” is exactly backwards.
And empty floor is a defect in itself. A wide room with nothing in it is worse than a small one, because scale without features only enlarges the emptiness. What a viewer counts is the density of features - structures, ruins, water, vegetation, changes of material. Fill every room with something before making any of them bigger.
Second, regularity. A lattice of equal rooms joined by straight channels reads as not having designed anything - and this has nothing to do with whether the pieces were authored or borrowed. If the parts are interchangeable and evenly spread, the impression is the same whatever they are made of.
Remember that space has a price: to a player, empty space is walking time. A large layout that is mostly gap is worse than a smaller one that is mostly content.
The third applies only to dungeon crawlers, but when it goes wrong it takes the genre with it. What makes a crawl feel like one is passing through a constriction.
The width of the opening between two areas has to match the corridor's. A 30-tile chamber bridging two rows is topologically one path and experientially one open space - nothing about walking it feels like passing through a door. Fix the path width first, then make every connection exactly that width: row to row, corridor to chamber, chamber to corridor. A chamber is wider only in its interior, never where it meets the route.
A bug from the same build, worth checking for: explicit connectors were removed because the chambers happened to provide the link, and when a chamber moved, three rows behind it were sealed off. If a connection is implicit in some other feature, it disappears the moment that feature does.
Fourth is decoration. Doodads can make a map or ruin it, and there is only one thing that decides which.
Decoration scattered at random positions is not decoration, it is noise - and it is worse than bare floor, because it actively advertises that nothing was composed. In a map that is dressed well the same pieces form things: wall segments run in continuous lines to enclose a hall, an archway sits in the gap where a doorway is, stairs lead somewhere, alcoves line up in a row.
The rule that follows is simple: place a decorative element by a rule that refers to the structure - along this wall, at this doorway, framing this platform - never by sampling a position. If there is no structural reason to put something somewhere, leave the floor empty.
One last thing: the system areas a player has to use - inventory, shops, a save pad - must be obvious on a whole-map view. Placed at true scale in a corner they are present and invisible at once, and that comes back as a real complaint rather than a matter of taste.
And one more, on the tools: the editor's terrain brushes are for broad ground, not for structure.
In the jungle tileset the brushes cannot make a walkable height change. Paint a plateau with any raised brush - Raised Jungle, High Dirt, Temple, High Jungle, High Raised Jungle, High Temple, High Ruins - and the inside is walkable while the edge is ringed with cliff tiles and unreachable from outside. All seven were tested and all seven came out cut off.
A hand-made map's ramps use tiles the brushes never produce - partially walkable cliff-transition tiles, which SCMDraft's ramp tool places. The jungle tileset reports no tiles flagged as ramps at all, so one cannot be asked for by name either. Multi-level terrain is therefore made by clipping and stamping: find a working ramp in a reference map, cut a small rectangle around it, and paste it across the boundary.
This is not only about ramps. Counted across one well-made jungle map, 38 per cent of its tiles are doodad-group ids outside the base tile catalogue - that baked structure layer is most of what makes it look built, and the brushes cannot reach it at all. Brushes for ground, stamping for structure: that is the division of labour when terrain quality is the goal.
Terrain complexity is itself one of the map limits. The editor's "nooks and crannies" error is not about running out of strings or units: it is the pathfinding pass that StarCraft runs at game start exceeding an internal bound. What runs out is how complicated the terrain is.
And it happens most on 256x256 maps. Finely carved terrain spread across a large canvas is exactly the combination that runs out - the same direction as this lesson's first rule, that a dense layout on a smaller canvas is cheaper and safer. When it fires there is no setting that avoids it; only simplifying the terrain does.
There are places in the stock tilesets where the height a tile looks and the height it is flagged as differ. The documented case is Tau Cross, where a strip of high-ground flag runs over the Outpost terrain and gives a lone Siege Tank vision, range and the high-ground miss bonus across a cliff. A tile looking like an elevation is not evidence that it is flagged as one.
A map whose long side is 96 or 192 does not fill the minimap and leaves a grey bar on all four sides. If the minimap's look matters, avoid those two numbers.
Why cliff tiles are so stiff to work with also comes out of their structure. The artwork differs per tileset but the layout inside one cliff set is always the same frame: top-left and top-right, bottom-left and bottom-right, the two ends, the inner corners, the pieces that rejoin after an end, and the top used when the wall zigzags - all in a fixed order. Vertically a cliff top is four rows per set and a cliff bottom six.
Inside that frame are substitute tiles used only when the cliff is one tile wide - a separate set above and below an inner corner. Narrow a cliff down to a single tile and the correct art is the substitute, not the ordinary corner. If a hand-narrowed cliff looks uniquely wrong, that is almost always why: not a wrong tile, but the narrow-case tile left unused.
And some sets simply leave an awkward gap - Space Platform's Low Platform cliff is the known one. The fix is to fill it from another set: copy the top of the wall terrain and paste it in, and the gap closes as wall. Convert the doodad to Terrain state before copying, and accept a one-row seam that comes with the copied tiles. It breaks under Carbot graphics.
Terrain modes