Terraforming The Alters: Last Variable with Blender, ZBrush & UE5

Introduction

Hello everyone! My name is Artem Ostapchuk, and I’m a Senior 3D Environment Artist at 11 bit studios. You might have seen my previous breakdown here on 80 Level about my Japanese Shinto Shrine personal project. Today, I’m back to share a look behind the scenes of environment work on The Alters: Last Variable DLC, focusing on the pipeline of filling our levels with lush vegetation under real production constraints.

Base Game vs. The DLC

On the base game of The Alters, I was responsible for building environment pipelines across several acts, creating meshes, materials, and internal tools - from anomaly-twisted canyons to interdimensional foliage veins only visible with a specialized flashlight. The main game's world was defined by its harsh, barren desolation, where players race to survive a planet-scorching sun.

In the Last Variable DLC, the story expands into terraforming. The environment had to work seamlessly in both its original barren state and its newly overgrown, terraformed version. My main focus was putting together the terraforming pipeline – making the foliage sets, landscape layers, master materials, a few helper tools, and dressing several areas across the levels.

Designing the Flora: Accelerated Growth

We wanted the vegetation to feel alien without falling into generic sci-fi tropes or looking like everyday Earth plants. Our narrative concept was simple: fossilized trees and dead alien soil get hit with a powerful terraforming liquid, triggering explosive, unnatural growth. This gave us a distinct visual language based on heavy moss accumulation, lots of branch structures, and coral-like vegetation spreading across the rock and trees.

Final terraform concept art

References & The Beauty Corner

Working from the initial concept by Robert Rejmak, we gathered references and built a dedicated "beauty corner" – a small test scene where we could test the assets, shaders, and terrain blending. Finding references was easy, it's incredible how many strange plants there are on our planet, and that was more than enough inspiration to ground our alien flora in a believable way.

Moving from base game to DLC, our core software stack stayed mostly the same: Blender and ZBrush for modeling and sculpting organic forms, and Substance 3D Designer & Painter for texturing.

For all our foliage, we relied exclusively on opaque Nanite meshes. That means no transparency – every small leaf and grass blade is actual cutout geometry. In our benchmark tests, this performed much better than using traditional masked shaders, so we went with that approach. Several assets also feature subtle World Position Offset (WPO) wind animation driven by vertex color channels – a technique I covered in more detail in my previous 80 Level breakdown.

As a team of three environment artists (with Patrycja Kusińska and Krzysztof Knysak), we each took ownership of different areas, so цу used additional tools like SpeedTree or Houdini depending on the specific task. I also like to use spline- and weight-based methods to spawn meshes in Blender's geometry nodes; it's a quick, artist-friendly way to create foliage assets.

And for landscape, like in the original game, we used VHM/RVT instead of Nanite landscape.

We didn't have a fixed schedule for making meshes. With only a few concepts and level designs constantly changing, we built the foliage kit on the fly and tested what worked and what didn't. The beauty corner we did early on gave us a clear picture of what we were aiming for, so whenever the spaces changed, we just added whatever new pieces were needed to make them work.

Designing for Scale & Custom In-Engine Tools

Since we didn't use the Houdini Engine/Live Link bridge directly into Unreal, we relied entirely on in-engine tools to scatter and populate the levels with flora. I created a few tools that greatly helped us with this task: PCG mesh scattering, geometry-script moss generation, and trace-based scattering. That helped us deliver a big overgrown world in a short time. We've also massively used level instances – reusing what's already created.

Technical Optimization & Global HISM Management

Generating this level of vegetation density in a short production window is only half the battle; ensuring it runs at smooth frame rates is just as critical.

A massive shout-out goes to our tech and engine department, especially Radosław Choma and Bartek Lipiński. With so many Blueprint prefabs and Packed Level Actors in the scene, we ended up with tons of separate HISM (Hierarchical static meshes) components split across different actors. While that works, it's definitely not the most optimal setup for performance.

To solve this, they developed a system that consolidates instances into a single global HISM per mesh type across the entire level and handles packed level actors. This ensured that everything runs smoothly.

One tip: Don't create packed levels out of actors with non-uniform scale if they have collision.

Main Challenges

The dual-state level design: Our biggest creative and technical puzzle was ensuring the levels worked in both their original barren/scorched state and their fully terraformed, overgrown state. Every vista, path, and tunnel had to be readable in both conditions without breaking player navigation or visual hierarchy.

Density of the level: There were quite a few new mechanics in the DLC, and players could place a lot more buildings in the world. So within the space we had, we had to make sure there was plenty of room for all that gameplay without making the environment look overcrowded.

What I Enjoyed Most

I think the most fun part was right at the beginning when I was working on the hero trees based on Robert's concept. We were still building our beauty corner, so the focus was entirely on nailing the visual idea rather than building a fully modular kit. Moments like that in a project are always great – you can just focus on interesting shapes and details without worrying too much about UVs or polycount yet.

Lessons Learned

Plan around your constraints: Know what your engine can and can't handle before making a bunch of assets. Building your assets and materials to fit those limits right from the start saves you a massive headache later when optimization time comes.

Invest Early in In-Engine Tooling & Quality of Life: If you can automate a repetitive task without sacrificing artistic control, it's always worth investing the time to build a tool for it. Simple quality-of-life features pay off just as much. Even a small, scriptable utility that hides unnecessary viewport overlays – saving each team member just a few minutes a day º is well worth the 15 minutes it takes to write.

Design with Adaptability in Mind (Think "What If?"): Things change constantly during game dev – mechanics get reworked, level sizes shift, and directions pivot. It's always a good idea to ask yourself "What if?" (funny enough, the core theme of The Alters) and build your assets and shaders with enough flexibility so you don’t have to start over from scratch when plans change.

Recommendations & Useful Resources

• Study real-world nature: First and foremost, look at real-world references. Studying actual corals, fungi, and unusual plants will give you much more interesting shapes, anatomy, and textures compared to the usual "glowing sci-fi mushrooms." When your alien flora follows real biological logic, it naturally looks grounded and believable.
• Alongside SpeedTree's YouTube channel and PrismaticaDev, which I mentioned in my previous article, I’d love to recommend Procedural Minds. If you want to dive into UE5’s PCG tools, it’s easily one of the best sources of practical knowledge out there.
• Reverse-engineer marketplace packs: Aside from YouTube tutorials, I really like picking up official Epic Games packs, or packs from Gumroad/Fab, to see what interesting things I can find inside. You can often discover clever ideas and completely different ways of building things.

Artem Ostapchuk, Senior 3D Environment Artist