Exterior Guidelines

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This page details how to create exterior landscapes in the style of Project Tamriel and Tamriel Rebuilt. Exterior landscapes are the first things that players see in the mod, so we must make sure we get them right.

Exterior modders create the landscape and all exterior spaces, including the wilderness, underwater, and city areas. Everything in an exterior cell, save for NPCs, are placed by exterior modders.

As with all Construction Set-centric developer roles, prospective exterior developers will need to pass an exterior showcase.

Make sure to also read the editor-specific tips and pitfalls on the Construction Set Tips page!


  • Exterior Modding Tutorial by Haplo – this is what you need if you want to learn how to make exteriors. Once you are through with that, see the below sections.

Showcase Requirements

Showcases must be made by all modders who work directly in the Construction Set and want to claim exterior, interior, or questing claims. Make sure you familiarize yourself with the contents of this page before you start your showcase.

The main requirements for an exterior showcase are:

  • The showcase must be a small island.
  • It must consist of six exterior cells.
  • It must have no more or less than two points of interest.
  • Your island should be emulating the style of one vanilla region.

In particular, pay attention to the following:

  • Object placement. Make sure you are properly placing objects so they don't float, bleed into things where not appropriate (use best judgement), or show back faces (the bottom or back part of a mesh which you can see through; in a review this will be called "caspering").
  • Editing the terrain. For showing off your terrain editing skills you are going to want to have a a nice, varied height landscape without jagged terrain or terrain spikes. The wireframe view mode (shortcut W) will help you spot these terrain errors.
  • Ground texture placement. Make sure that the textures you place are region appropriate, and are blending properly. When three or more textures touch in a corner you will get a texture seam; these are often unavoidable and should be covered with statics such as rocks or trees. (Texture seams become easier to spot when you hide statics with Shift-C.)
  • Vertex shading. Your objects should have region appropriate shading beneath them (in the Landscape Edit window, with Edit Colors ticked on, you can Ctrl-click to copy colours). Most land textures will also have an outline with vertex shading; while this isn't common outside of roads in vanilla, its best to get into the habit of doing this.
  • Sinking and detailing your roads. While roads may not always end up sunk in the world for various reasons, its important to show your ability to sink them. Take a look at the Ascadian Isles Region for a great example. Roads are also usually more detailed with rocks and flora than other areas.
  • Pathing. Make sure players can actually traverse the land you make. You can explore your island with an Altmer or an Orc to test if there's anywhere you can get stuck. Pits should also have a way out.
  • Points of interest. Your showcase should have 2 different types of PoI, such as towns or dungeons, that have more pieces than just an entrance.
  • Assign your region to each cell in the World / Exterior Cell window.
  • Have a pathgrid in the cells with your PoIs (see the Pathgrid Tutorial in the Interior Guidelines; the process is very similar for exteriors).
  • Make sure your file is clean (using, e.g., TESAME).
  • Aim for the same level of references per cell as the region you are copying.
  • Don't set mix in your PoIs. While this isn't always forbidden, it's important to show your skill with a more limited set.
  • NPCs and creature spawners are not required.
  • Tamriel_Data is allowed. It can be nice to familiarize yourself with the new assets your claims will have once you pass showcase.

Once complete, the plugin (.esp file) containing your showcase island should all be posted in the Showcase Forum of Tamriel Rebuilt or Project Tamriel. You should post exactly one showcase thread, in which you can display however many of the three types of showcase you would like.

If your showcase has not been officially reviewed or it seems to be taking a while, please bump the thread as a reminder, or mention it in the showcases channel on the respective Discord server. Sometimes we forget!

Claims as Showcases

Experienced modders can ask about taking a claim for their showcase (the Discord server of the respective project would be your best place to ask) if the following points are met:

  • Proven experience. This could be a passed showcase of another area of development work or a link to your published or personal mods.
  • Open or openable claims.
  • The claim would preferably be on the smaller side, and the 2 PoI maximum would not apply. The 2 PoI minimum, however, is still required.
  • The claim should not have (much) previous development work done. A claim somebody dropped after doing a cell and a half is fine, but one that is half completed or has every PoI finished is not fine.
  • No overhaul claims. Places such as Solitude Forest are handled differently and will not show off the same skill set as creating your own exterior.
  • An eligible region. A showcase-able region should have plenty of completed cells for you to reference so you aren't left in the dark with how to design your cells.
  • Constant updates. Ghosting will get your claim revoked. (This is also true for developers.)


  1. Find a claim you want to work on and claim it. This can be found on the Tamriel Rebuilt claims browser or the respective project's exterior forum on the Project Tamriel website.
  2. Load needed files:
    1. Vanilla files: Morrowind.esm, Tribunal.esm, and Bloodmoon.esm.
    2. Tamriel_Data.esm – specifically, you will need to download both the released Tamriel Data that contains the three .bsa files and the TD_Addon, which contains new loose files and an updated Tamriel_Data.esm file.
    3. Your own claim plugin (.esp file).
  3. Read the relevant region guide to know which elevation changes, textures, vertex colors, flora, and rocks to use and how.
  4. Raise the terrain above the water. Check the claim description for how high or low you can go with your landscape. Often, for a claim, the terrain is already raised for you, as heightmaps are commonly made prior to claims being opened. If that is the case, keep in mind that you don't need to stick to the heightmap religiously – unless specifically instructed, you can change the locations of mesas or slopes as you want (but see the point about bordermatching later).
  5. Look at the claim description and the gridmap to know which points of interest you need to add. Map out roughly where you want to add them on your claim. You can also suggest moving some PoIs to neighboring claims or dropping them altogether, or adding new ones in. This needs to be coordinated with senior developers on Discord.
  6. Look at neighboring claims and section files, if any are complete or being worked on, to see what general types of landscapes and elevations you need to have near you claim edges. We don't want to end up with overly abrupt changes on claim borders. If the landscape in neighboring claims doesn't work for you, you can coordinate with senior devleopers and respective claimants on Discord to have them changed.
  7. Roughly set the general elevations of your claim.
  8. Add roads and already sink them in properly. This will be much harder to do after you have placed a ton of statics around them.
  9. Start adding textures, vertex colors, and static objects. It is up to you in which order you want to work on points of interest vs. wilderness areas. You can also place textures and vertex color immediately for the whole claim, or work on more or less finishing everything, including detailing, for a small patch of land first before moving on to the next. You just need to have a larger picture of the claim in mind while you do this.
  10. Bordermatch with neighboring claims and section files. This means adding the neighboring row of cells from each neighboring claim to your own claim, editing the terrain, statics, etc., to seamlessly transition, then cutting the extra cells out of your own claim and adding them back into the neighboring ones.
  11. Assign regions to all your cells and names to all points of interest that need them.
  12. Add path grids for NPCs and creatures around points of interest.
  13. Walk around your claim in-game to check for navigation issues.
  14. Check for land spikes, floaters or unfitting bleeders – i.e., do an overall sweep of your claim to make the reviewer's job somewhat easier.
  15. Clean your plugin with TESAME, Esp-QuickEditor, or tes3cmd.
  16. Put the claim up for review! It can take a while to get a reviewer to take a look – we are currently very low on exterior reviewers (as of this writing in May 2023).

Common Guidelines

There are some common things to watch out for, when making exteriors:

  • Keep the terrain smooth – get rid of terrain spikes and pits. Sometimes you need to have stretched terrain in areas with big elevation changes, but generally terrain should be smooth.
  • Use radius 2 for vertex shading – radius 1 looks too blocky.
  • Group the flora in the majority of cases – also generally place them near statics, like rocks and rockgroups.
  • Don't overdetail – less is often more. Vanilla keeps things simple and so should we.
  • Be wary of terrain seams – they tend to appear when three textures meet at the same spot. Cover them completely with statics (or try preventing them to appear – it will come with experience).
  • Walk around your claim! A lot of the common issues in older Tamriel Rebuilt and Project Tamriel exteriors are due to exterior developers neglecting to view their exteriors from the ground level.
  • Have fun! Exterior development is the most pleasant kind of work, when you understand your tools and how to use them well.

Design Philosophy

Tamriel Rebuilt and Project Tamriel have gone through twenty years of changing standards and expectations for exterior development. There have been periods when we didn't know nothing about nothing. Then there were periods where using vanilla assets in very unintended ways was expected, with every exterior developer encouraged to get "creative." Then there were periods where our goal was to make significantly more detailed or "popping" exteriors than vanilla did, which resulted in tons of static meshes being strewn over the landscape. As the years went on, the standards kept changing and prior paradigms in exterior design kept getting critiqued. Vanilla, however, kept looking the same through all this time.

Hence, our modern thinking is to use the same design language as vanilla. Not only do we hope that this will allow us to produce more future-proof landscapes, but it helps us achieve three important goals:

  1. Coherency with the vanilla game. Players shouldn't find that things are substantially different on the mainland – at least in the immediate area when leaving Vvardenfell. Even in distant provinces, this should be the goal.
  2. Ease of navigation. Vvardenfell is easy to navigate. You always can see where you can go, or if you want to walk off the path, you can at no penalty. In contrast, some older bits of Tamriel Rebuilt and Project Tamriel tend to overuse cliffs and mountain meshes that the player cannot walk over, meaning they need to make long detours or levitate, nor are the paths as easy to find as on Vvardenfell.
  3. Performance. Frame rates drop a lot in certain areas in Tamriel Rebuilt and Project Tamriel. Two areas in particular are Old Ebonheart and Roa Dyr. Largely this is due to poorly optimized building meshes and city setup, but the densely packed exterior around Roa Dyr most likely contributes to the slow down also.

You might think that vanilla design language will cause us to produce same-y landscapes. That may have been the case once, but now we can rely on our busy asset developers to produce mostly unique assets for each region. After all, this is how vanilla did it.

[Cicero's thread: https://www.tamriel-rebuilt.org/forum/exteriors-feedback]

Terrain Editing

Terrain editing is the bread-and-butter of exteriors. Terrain should be varied and look good on its own, even before you add statics.

Sight Blockers

TES III relies on a lot of minor height variations in the landscape to act as sight blockers for the player and make the world feel bigger. If you don't have anything to obstruct the view, you are making the area boring for the player, as they will end up looking at the same piece of landscape for 20 minutes. The only way to really tell if your sight blockers are working is to walk around the landscape in-game.

Mostly for the same reason, make sure you sink roads into the landscape a little bit. Vanilla almost always does it, and like above, it helps makes the world feel much larger and hides things from the player, making them want to explore.

Take a look at the Ascadian Isles Region for all-around great examples on road sinking and sight blockers.

Navigational Planning

Vanilla does a lot of influencing the player's movements with its terrain height. The northern Ashlands do it exceptionally well, most of the time guiding your path to certain roads while allowing freedom, but also closing in to a choke-point, at Zergonipal. It is always good to have an idea of how your landscape is going to force the player to travel, and even to plan around it where you can.


Terrain editing should generally be done with an editing radius of 3. Radius 2 should only be used for touch-ups and in particularly constricted areas, whereas radius 1 is almost never used. Use larger editing sizes when you need to raise terrain at the beginning of you claim work.

Watch out for terrain spikes and pits! These are one of the most common issues that starting exterior developers have. Use the wireframe view (shortcut W) to identify them and the smooth tool to remove them.


Use appropriate texture for the region that you are working on (see "Region-Specific Requirements" below).

When three or more textures touch in a corner you will get a texture seam. These are easier to spot if you view the wireframe (W key).

With experience, you will be able to have less of these. Still, they are often unavoidable and should be covered with statics such as rocks or trees.

Terrain Glitches

Sometimes you will encounter a maddening Construction Set bug, wherein working on the edge of your exterior claim, the Construction Set will suddenly lower the elevation of an entire cell's landscape by a considerable margin.

The only remedy against these bugs is to save early, save often, and keep backups! Also, turn on automatic backups in your Construction Set.

Sooner or later, all exterior developers will learn the hard way how important this is – usually after they have lost hours of hard work to this glitch.

A lesser issue is when the landscape on the very edge of your claim will suddenly drop to elevation 0, causing an extremely steep drop with ugly texture stretching. This can be laboriously fixed by using the smoothing tool in a very careful manner.

Never Do Exterior Caves

Old Tamriel Rebuilt and Project Tamriel had the bad habit of doing caves in the exteriors using large rock meshes. We are aiming to remove almost all occurrences in the future and to avoid adding new ones.

While exterior caves can look good at first glance, they are very hard to review, often cause you to go overbudget on static usage, affecting performance in a bad way, and are typically difficult for the player to find and navigate. They will also break immersion whenever it rains or snows, as the meshes above do not block this.

Vertex Shading

Instead of doing blocky vertex shading (left), go diagonal and rounded (right).

If terrain editing is half of the look, vertex shading is the other half. Don't neglect it; it will help make your exteriors pop so that you don't have to overuse static objects.

Vertex shading needs to go between (almost) every texture transition (especially with roads), in steep ground recesses and crevices and around the bases of large rocks, trees, and buildings. Tamriel Rebuilt and Project Tamriel does this a little more consistently than vanilla.

A vertex shading radius of 2 is best, as radius 1 looks too blocky.

Textures in Morrowind are per-tile, but vertex shading should help smoothen this jaggedness. Instead of following the texture transition to the T, go diagonal and round our the transition. See the image to the side.


Vertex color is encouraged – a simple black shade over brighter and more saturated textures looks tacky a lot of the time. Find the appropriate vertex color from the Region-Specific Requirements (below), or copy colors from existing exteriors in the Landscape Edit window by Ctrl-clicking with Edit Colors ticked on.

Don't forget that vertex shading changes based on context:

  • The lighter the region palette (snowy regions, for example), the higher these RGB numbers should be.
  • Swamps should use lower RGB numbers for darker colors.
  • Coast line shading, underwater static shading, and underwater texture border shading are usually all different from above-ground variants.
  • Under freshwater rivers or lakes, or near grotto entrances with custom lighting, some blue or green vertex colors are allowed.

If these details aren't given in the region guide, pick the vertex color from similar situations in existing exterior claims of the same region.


Some examples from Ascadian Isles showing how to make roads look good.

Roads deserve extra care when making exteriors, as these are where most players will spend most of their time.

A well-made road/path needs a few important things:

  • A reason to exist and a logical route through the cell(s). Is it logical that someone made a road here, or would it have made more sense to go the other way?
  • Don't feel the need to stick too closely to the gridmap routes. If you are devleoping a claim from scratch, you'll want to include the roads on the map, but instead of sticking to their routes perfectly, make sure the road makes sense in-game. Maps will be changed later to reflect your implementation.
  • A smooth, curving path. You should not do perfect 90-degree turns and perfectly N-S or W-E trending roads.
  • The road needs to be lower than its immediate surroundings (as if worn down by constant wear and use).
  • A vertex-shaded "outline," but don't make it blocky – see the above section.
  • Detail (and optionally, some points of interest) along the way, using static rocks or fences, or flora. This will make walking along it enjoyable, and will give you a feeling of "not wanting the road to end."


Conserve Detail

Detail is good, but letting the scene breathe and not having everything struggle for focal attention will always look better in regular play and will provide better frame rates. Avoid what is called "nervous cluttering" – where a claimant feels a place looks too bare in the Construction Set and will, without guidance, fill it with random statics just to not have an empty patch.

The standard accepted "minimum amount" for a (non-seafloor) exterior cell is around 100 references. A healthy number is around 150-250.

The key to making your cells look good with this few references is having a good landmesh – statics should not be doing the heavy lifting in most scenarios. If your scene requires a lot of static cramming to look right you could probably stand to space things out a bit more.

Moreover, most detail should be placed near roads (either explicit roads or implicit paths that the player will likely travel along). Since players will stick mostly to roads, this will allow you to use your detail budget in the most effective way.

Conversely, the tops of hills should generally be left bare – vanilla uses this effectively to make

Commonly Overused Asset Types

  • Rock groups – these are one of the more common things that exterior developers overuse for easy detail. Make sure to use them sparingly, like vanilla does. It's okay to let the landscape breathe, not everything needs to be covered in little bits of rock.
  • Cliffs – these are also easy to go overboard with. Even in the most mountainous areas, cliffs shouldn't cover more than half of the landscape area, except for places where extreme height differences cause too much texture stretching on the land mesh – but even then, you are better off spreading things out a little more and making the slope a little less steep. Large rocks are wasted space, and wasted opportunities (unless they are used to block off areas on purpose). Instead, create little natural alcoves and balconies with hidden secrets. Give a feeling of depth using vertex paint. Use space to your advantage. Never just put a bunch of rocks/cliffs and call it a day.
  • Rock arches – these looked cool in West Gash, but they should stay a West Gash thing. Very old Tamriel Rebuilt was notorious in sticking rock arches absolutely everywhere – let's not do so anymore!
  • Water above 0 elevation – these can sometimes look good, but are very difficult to pull off, yet are extremely common in some older exteriors. The exception are regions that are explicitly meant to have large amounts above-0 water, but even then, it's very difficult to make them look decent.
  • Waterfalls – these should be nice little surprises for the player. If they are too common, it will ruin the feeling. Besides, a lot of our older exteriors have waterfalls coming out of nowhere and ending up in a small, stagnant pond. Instead, if waterfalls are added at all, they should mostly be on rivers.

Avoid Scaling Statics Too Much

You should rarely go above scale 1.3 for rocks – the difference in texel density will become easily noticeable for players. Aim for an average sclae size of 1.00, but don't be afraid to sometimes scale rock clusters down to as low as 0.5.

That being said, you should use different scales to make things more varied. You can put rocks close to one another in formations, playing with scale and using low numbers to create more detail, and leaving gaps between different formations for navigation.

Group Flora

Group the flora in the majority of cases to create clumps, instead of spreading them out evenly. This will make the terrain more varied and "realistic" looking.

Also, generally place flora near other statics, like rocks and rock groups. This is especially true with container plants, which should cluster together near rocks, making it easy to find them.

Keep Pathing In Mind

Players will need to actually traverse the land you make. You can explore your claim with an Altmer or an Orc to test if there is anywhere you can get stuck. Pits should also have a way out.

This is another place where being conservative with static mesh usage is helpful – landscape is much easier to traverse than a mish-mash of meshes.

NPCs, too, will need to be able to traverse the landscape – for that, make sure to add path grids around points of interest. See the Path Grid tutorial in the Interior Guidelines – the process is very similar for exteriors.

No Set Mixing

Very old Tamriel Rebuilt had the bad habit of mixing different styles/cultures of architecture together in its settlements to create unique set pieces or more variety. Vanilla doesn't do that (outside of Gnisis, which is unique in many respects), and neither should we.

When you need a unique setup for your exterior, you should instead put in an asset request – we have many talented asset developers that can help you.

Avoid Bleeding Grass

A common issue in some exteriors was grass meshes being "bled" (partially sunk) into the ground too much. The common stem of the grass mesh should remain slightly visible, not only the individual leaves.


Exterior claims should have lights in settlements and in some wilderness areas.

A forest doesn't need lots of light – one or two for a neat ambient effect is enough.

In towns, you shouldn't go overboard but don't make it so dark you need the minimap to find doors! Use light sources like lamps, torches, etc. Make sure they are properly sunken into the ground, placed on a surface, or hung from some sort of a pole or rope. For example, when creating an open dock for a town, make sure to add plenty of lights along the edge, so players know where to step, and so ships can make port easier:

Region-Specific Requirements

Each Tamriel Rebuilt or Project Tamriel region has its own texture, vertex shading, and asset usage expectations, which need to be adhered to. Usually, these are established by the first claimant to complete an exterior claim in said region in cooperation with asset developers.

Sometimes, the region-specific guidelines will be modified mid-way through the development of a region – in that case, it is up to (senior) exterior developers to retrofit the changes into older claims.

You can find these guides on each region's wiki page (e.g., here for Tamriel Rebuilt).

Other Resources

Guide to using the Hlaalu modular building set by Chef

Collection of feedback from our exterior developers and establishment of standards by Cicero