While making levels in NSMBWii, it is important to be familiar with tilesets. Making errors with tiles will make your levels look unprofessional. This list shows some common tiling errors that can be fixed with ease.
This image shows how tilesets usually work. This is very important information for newcomers wanting to fix their tiling errors. Of course, custom-made tilesets sometimes vary from this basic structure, but it is still helpful to know.
Visual Tiling Errors
Using the corner tiles is very important so that levels don't look unfinished and generally ugly.
Here is another corner error, this time on the insides of the corners.
Very small holes in the ground simply look odd. Holes should be wide enough for jumps, not too thin.
Though it may seem obvious, some people don't know how to make multiple decorations on top of each other. Simply using different layers will fix this problem. However there shouldn't be too much layered decoration in a level.
Mushrooms should always be placed one tile inside the stem. It is also important that the stem has the correct thickness depending on the mushroom platform it is connected to. Another thing to note is that the thick mushrooms shouldn't be used as platforms with a short width as it may look weird. In those cases, thin mushroom platforms should be used instead.
Mechanical Tiling Errors
When a POW-block is used or multiple players perform a ground pound at the same time, the screen shakes, so all tiles must be extended one tile outside of the zone border to ensure no graphical problems. When pits are added to a level, Mario dies only after he falls beyond the zone, thus, walls outside of the zone should be extended by four tiles.
The top of the screen extends about 8 tiles above the zone, making "above-the-zone-secrets" as seen in 1-3 of NSMBWii possible. This is important to know as the player could walk above the stage to skip it entirely if the walls are not extended upwards by the amount required.
When adding layer 2 solid-on-top tiles next to slopes, there is a possibility of having the player glitch through the floor with the small gap. Adding invisible tiles in the corners will help.
Coin and Block Errors
It is good practice to place blocks three tiles above the ground, not two.
Coins should definitely be placed in levels, otherwise the levels feel quite bland. However, they shouldn't be overly used in single locations. Coins should be thoroughly dispersed throughout the level, perhaps in jump arcs. Alternatively they can also be placed on the ground, but they shouldn't be right at the edge of a platform.
Another styling tip for coins on top of blocks.
Background Rock Errors
While the 1x1 filler object of background rocks is randomized ingame, it is better to also use the bigger rock objects the tilesets have to offer. However the same big rock object should not be repeated over and over again as that can look boring, lazy and can potentially lead to cutoffs if not tiled properly. Therefore rocks should be diversified and stretched to their correct sizes.
While background rocks do look pleasing, they should have the proper borders around them.
Background rocks should also not look too flat.
Rectangular Stone Block Errors
Sometimes, people like to decorate their levels with stone blocks inside the ground. This is a pleasing decoration but only when done right. The background should be filled in (usually with rocks) to prevent gaps that reveal the background of the level.
Another error with stone blocks is when they are too big. Smaller stone blocks should be used more often instead. Though it may seem more time consuming, it will result in better looking decoration. Also, blocks of the same type should rarely be placed directly next to each other unless it can't be avoided.
Warp Pipe Errors
Pipes should always connect to solid ground. Alternatively they can be extended outside the zone to make it look like they connect to another part of the level.
This image of pipes has two problems. The yellow pipe should be fully behind the ground and the green pipe shouldn't jaggedly cut off the tiles of the ground. The hole that the green pipe makes should also be partially filled with background rocks. Another problem to some people is that they don't like seeing these two ways to make pipes go into the ground right next to each other, so only one option should be chosen per level.
Tower Tiling
Tower tiling has a system to it. There are always colored blocks on the outside and the inside is filled with gray blocks.
It is also important to make the ground and walls of towers not too repetitive. Though it is time consuming, it's going to look much better than just repeating the same object over and over again.
Tiling layer 0 secrets is also very important. Secret paths should always be behind colored blocks. The general outline of the secret should also be somewhat traceable by just copying layer 1, pasting it onto layer 0 and then filling the empty spaces with colored blocks.
Airship Tiling
While tiling with an airship tileset, it is important to note that the planks as seen at the top should only have their wavy side exposed to the air. Another major aspect is to have shadows underneath the outline as demonstrated at the bottom half of the image.
Inside corners of airships always have a sort of plus (+) shape. Shadows should be added accordingly as seen underneath the horizontal planks. The background walls also have shadows along all sides except for the bottom. Another thing to note is that planks should have a length of around ten tiles. Also the bigger planks should not be used too frequently.
If there isn't at least one tile of space between the plus shaped inside corners, then simpler corners are used instead.
Tiling Opinions
When using beach tileset platforms, they should always be arranged so that both halves extend equal lengths. This can be avoided by having two support logs instead.
When using specific tilesets, there are all sorts of things that can help to make the environment not look empty. These decorations shouldn't be used too frequently though as a lot of people dislike having too many decoration objects placed throughout a level.
