BioSuit

Project

When I saw Victoria Yurkovets’s concept for the first time, I instantly fell in love with it. I love the details and colors and how all these organic forms have a sort of grace and charm from my perspective. So, I decided to create the most detailed character I could.

Goals

1. Create the most realistic and detailed game character that can be done from this concept.
2. Adapt this model for Unreal Engine 5.
3. Create custom shaders for organic surfaces.
4. Create a rigging system that can control all limbs.

Blockout

I would say that this was the easiest part of the project. It all started with one large blockout that covered all the medium details and limbs of the character.

Then I cut this blockout into medium-sized pieces: head, body, arms, legs, tail and left and right blade, to add extra details to each. After that, I cut those medium pieces into small ones, which would be the primary details for the high-poly model.

The main tasks were to keep the proportions of the character the same as they are in the concept and add all the details from the concept. Essentially, replicating the concept as much as possible.

I mostly used the Standard brush, Clay brush, Dam Standard Brush, and Trim Dynamic Brush.
The Dam Standard Brush was a lifesaver while sculpting the bulges and cavities of the organic form. It made it easy to achieve the shape of tissues or muscles.

One major challenge at this point was to recreate all the details of the arms and legs from the concept while keeping them symmetrical and functional for future rigging.

As you can see, the arms in the model and the concept are quite different because I realized that the way they were made originally would not work properly when I have to put a skeleton inside the character.

Next, I had to work on the tail to make it look the same way as in the concept but also make it shorter because it was too long. Even after that, it is still the longest part of the character.

The tail itself does not have a fully repeated pattern. It has segments with different patterns.

While I was in the sculpting phase, I decided not to sculpt small and tiled details for organic surfaces.
The reason for that is that I wanted to add small details in Substance Painter, as I have more control over tiling textures there compared to ZBrush.

Retopology

During the retopology process, I tried to keep two ideas in mind:

First, it had to use custom shaders in UE5 with vertex animation to make the organic surface move as if it’s alive (for that, I had to make high-density retopology in certain areas).
Second, I wanted to replicate all possible shapes from the high-poly model onto the low-poly model, while still keeping the model suitable for gaming purposes.

My favorite software for a long time has been TopoGun, as it has the fastest and most efficient controls over polygons. The final poly count was 114k.

As I mentioned earlier, while I was sculpting, I separated the high-poly model into sections (folders): head, body, legs, arms, back blades, tail and cannon, for the convenience of sculpting and optimization purposes.

So, I decided to use these groups as a partially high-poly reference and create a low-poly model piece by piece, loading different sections. For example, when I finished the retopology of the body, I had to load the leg’s high-poly model into TopoGun and proceed with the same low-poly mesh.

Unwrapping

Software: RizomUV. When it’s a personal project, you don’t need to limit yourself in the number of textures. So, to achieve better quality, the best way was to split the character into ID maps, where each map represents a different part of the model with separated UVs.

My character has 8 maps with 4k resolution, and 1 map of the spider with 1k resolution.

Baking

I’m using the classic method of separated baking, which means splitting the character into pieces and baking maps piece by piece.
Usually, I split some small parts that can have unnecessary occlusion effects. Similarly, with the normal map, I prefer to make a split normal map and then combine it in Photoshop.

In addition to the standard maps, I baked a specific thickness map to help add extra organic shades to the painted layers. This type of map was created by sculpting an extra heavily smoothed mesh inside the high-poly mesh in ZBrush, like matryoshka dolls.

Texturing

The biggest and most difficult part of the project was texturing. I constantly switched between Substance Painter and Unreal Engine to see the results and make adjustments to colors, roughness, and other material properties to achieve the desired result.

In my case, the result in Unreal Engine took priority over the result in Substance Painter.

Color Masking

Since the concept art did not represent any sort of shade or material identification, I decided to paint an RGB mask and use it to specify organic surfaces.
These masks were not exactly used in texturing but helped in the future to separate colors and surface shades.

I split all the surfaces into three groups: Red – the softest surface, similar to human mucous tissues. These zones have shader animation in the future. Green – medium hardness surface, similar to lizard skin. Blue – the hardest zones, such as bones, claws, and carapace.

I wanted to create a material that looks organic and alien at the same time.
For that, I used references from movies (Alien 1979), games (StarCraft 2), and real anatomy (cell pictures).

I made several attempts to create the main skin surface, but most of them looked like lizard or crocodile skin, which I didn’t like.
Finally, I made a material in Substance Designer that looks like alien skin and can be used as a base color mask to create that alien pattern skin design.

The next step was to create white tissues on the flesh, similar to the egg from the Alien movie. I created a mask in the same Substance file, but with a different node’s route inside, and used this mask as a tissue layer.

I figured out that the green shades that were in the concept were not the best colors for the full paint of the model, so I decided to stick with colors that represent blood: red, yellow, and purple. Green had a small place around the upper arms, and gray was used as a color for more durable places like carapaces.

The main task was to stick with the color palette that I chose before, but also keep the colors as close to the concept as possible.

To create the noisy roughness effect, I used the same layer as the Alien Skin but tiled it x3.5.
To make the tissues look more distorted, like real flesh, I used the “Warp” modifier.

For the horns and claws, I used a grayscale mask called “Cells 1” with a height modifier, and I applied the Wrap effect to create random distortion as found in nature.
I wanted to create a durable and hard surface that could visually sustain a lot of damage and also provide damage itself.

Shaders

My main goal with the character shader was to create a shader that looks alive, like a breathing and pulsing living being.

While I was in the process of retopology, I decided to take a quick detour to create a base for the shader and test it on a small model. In the first iteration, the shader didn’t have any masks because at that point, I wanted to figure out how I could create an animated veins effect.

Later, when I had finished texturing, I upgraded the material with additional math, colors, and necessary masks.

created two masks: an RGB mask for subsurface and vertex animation, and a separated tiled veins mask.
The RGB mask was drawn in Substance Painter, for which I added an extra custom layer called SSmask, and a Veins mask.

I had to use a separated veins vessel mask for the Height from Normal map node because it had to be a textured object in order to work.

To create the effect of floating blood in the veins, I used a Noise node with the Time node as an extra mask.

Eyes

I made many attempts to make the eyes as close as possible to the concept while also showcasing personality. However, all of them failed until I realized that I shouldn’t sculpt them. They should not be modeled; they have to be made from a shader.

I didn’t have many references on how the eyes should look, only a vague image in my head. Since I wasn’t sure exactly what I wanted, I decided to make the shader as flexible as possible. The character has 8 eyes in front, 4 on the jaw, and 5 on the back of the head, so I used the same model for each eye.

Skeleton

I’m not much of an animator, but I know the basics of skinning and rigging. Usually, I use the biped system inside 3ds Max, but for this project, I switched to the CAT skeleton because it has better controls from the pelvis to the spine, unlike biped.

I used a mixed skeleton with CAT (base skeleton), Point Helpers (extra bones), and Standard bones (for the tail only). In summary, this character has about 300 bones.

For a character like this, the best way to create a basic weight setup is to use a proxy mesh: a low-poly mesh that covers all the necessary parts and creates a projection of vertex weights for the denser model.

Unlike the four main eyes, the small eyes have a different anatomy, and to create a video animation of blinking eyes, I needed to create a unique bone structure for them.

I came up with the idea of pulling and shrinking, where the eye gets sucked into the head and the external mesh scales down to imitate blinking. So, each small eye has three bones: Puller, Rotator, and Shrinker.

Rendering and Posing

Unreal Engine is the best solution for 3D artists when it comes to model rendering. Yes, it’s a bit more complicated than Marmoset Toolbag, but on the other hand, it gives artists more freedom to create specific shaders and environments that will help create the best preview.

I wanted to recreate the same pose as in the concept and also add my own extras. Since I didn’t know what kind of lighting I wanted, I created several sublevels with different lighting setups to see what would work best. The main idea behind this was to avoid making the character look flat and to represent the alien surface as if it were alive.

The final renders were made with Cinematic cameras and the Movie Render Queue, which is the best feature to render images and videos as large as possible.
Unreal Engine is known for its slightly blurry renders, so for my model, I’m using a sharpness shader in the post-process volume.

This wonderful tutorial helped me to create it.

Conclusion

It was a wonderful experience creating this character. If someone asked me to recreate it from scratch, I would do it. I was able to achieve almost everything I had in mind regarding the concept: the vision, materials, and the character’s feeling.

I would like to thank GameArtists.co.uk for inviting me to write this breakdown for character artists.

Thank you for reading, and I hope that some ideas from here will help you in future projects.