BIOMUTANT - - Ideas for Potential Modding (1st edit!)

A Rex Saboteur darts in and out between waves of enemies, the resulting buoyancy from their inflated body allowing them to dash greater distances. One mistake, however, is all it takes to bring them out from the fight. A second fireball shot from the mouth of some monstrosity makes contact, leading the Rex’s form to swell all the more. Their attire having burst at the seems, they can’t help but bounce around uncontrollably, hoping their body would hold just as the third fireball was fired.

Munching on their supply of taffy, a Hyla Commando watches on as their body skyrockets in weight. Taking a seat, they make the most of their increased vitality with an automatic firearm in hand. Attacking waves of enemies soon find themselves pelted with radioactive shelling - - wreaking havoc among their ranks as they begin swelling, bloating and even fattening into variously grotesque forms. Breeds from the Hyla strain weren’t usually this smart, but then again… a cunning plan isn’t exactly hard to come up with when you have a weapon like this.

Elemental damage? Check. Biohazardous mutations? Check. An ultra-increased intellect to cast said abilities, with the only downside being extreme bloating + the occasional gaseous outburst? Double check. The overfilled, Fip Psi-Freak confidently strides into the camp, an angry flurry of spells as well as abilities being hurled towards any who come near. The increased intellect they amassed meant running out of ki would take a while, and none would be spared in the meantime. With their hands brought together to charge an especially powerful cold spell, they cackle then belch in a cocksure manner as any remaining combatants flee - - as fast as their already swollen forms would take them.

BIOMUTANT is a game which released on May 24th and is something I’ve been… somewhat obsessed with completing 100% of. Whilst playing, I stumbled into one of the game’s various hazard regions and it got me thinking on whether an expansion mod would be possible based on the various status effects. Heat, Biohazard, Cold, Goo, Asphyxia and Radiation are the ones which come to mind. From there, it was just a case of seeing how these would cause different types of expansion, how this would be balanced making use of the game’s pre-existing mechanics and lastly how the player would manage this third system of * bloat.* Quite the thought experiment.

As was kindly pointed out to me, it should be kept in mind that the game doesn’t currently have its own API/other modification software. The idea I had in mind originally would have required one, this being to take advantage of the character’s various body sliders (arms, chest, thighs, abdomen, etc.) or, alternatively, to rebuild the character’s body from the ground up (where the sliders could then be incorporated). That being said, BIOMUTANT isn’t too old a game. It shouldn’t be too long before an API is released, but still - - I do encourage everyone to take the following with a grain of salt (with the worst case scenario being an API is never released, but this remains a fun writing exercise). In an ideal world, these 5 different expansion types would stack on top of each other resulting in various shapes - - but since I’m not completely insane (my god, this is already gonna be tons of work), a system in which the player switches to the expansion type of the last status they came into contact with should work fine.

Story wise, all I have is that the heavy amounts of pollution in the world have lead to some of the races in the game to mutate + bloat into shapes and sizes unrecognizable. That is, upon coming into contact with the aforementioned status types. The different types of expansion each of these can cause are listed below.

Expansion Types: Heat damage slowly leads to the player mutating into a part hot-air-balloon . The expansion effect starts in their stomach, before scaling with the rest of their body until they’re orb shaped, glowing red-hot and floating upwards. Stat bonuses as their expansion progresses are an increase in agility, coupled with a decrease in vitality. Biohazard damage, on the other hand, leads to the player developing more of a bottom-heavy shape. Other side-effects include a sickly-green glow and… the occasional gaseous outburst. Gross. Overall intelligence increases with size, but these outbursts lead to a drop in charisma. Cold damage was a little funky to figure out, so I settled with it mutating the player into an “ultra-cold” water-balloon. Unlike the orb shaped expansion from the heat status, cold damage leads to the player’s stomach becoming their most prominent part as they continue to expand. What you can expect is an increase in charisma… presumedly on account of their minty-cool breath, but a decrease in strength to boot.

Goo not only results in swelling, but also muscle growth across various parts of the body. This still leads to the player becoming immobilized, presumedly due to mass amounts of undigested goo building up in the player’s body, thus giving them more of a fattened, overfilled shape. This increase in strength goes without mentioning, though a decrease in intelligence balances this out + fits with some of the other creatures found in those goo/oil zones. Asphyxia hazard zones (AKA, “Deadzones”) are heavily polluted areas of the game which the player is unable to breath in. This can be mitigated via the use of a certain suit, albeit, with this mod it does nothing to stop a fattening mutation from seeping through into the player. This adds an extra layer of challenge to the zone, with the suit being more durable than other pieces of attire (will discuss later in “bloating management”) but requiring the player to keep their bloat level as low as possible. This effect can also be attained by consuming some of the lesser health/energy items, such as taffy and energy drinks. Weight gain results in an increase to vitality what with all the extra fat, yet a decrease to agility as time goes on. Radiation is the last, not quite having an expansion type to call its own - - rather, it cycles through the aforementioned expansion types in periodic fashion. These will either stack on top of each other or switch to the latest type every few seconds, resulting in events that can only be deemed wildly unpredictable.

Bloating Management: Bloat is a third management system, similar to health and energy, only the player works to decrease it to more manageable levels via the use of special consumables. At 0% the player is at their base, at 25% their clothing tears apart (unless they’re wearing one of the hazard protection suits), at 75% they become immobilized (this is where hazard protection suits tear apart) and at 100% they explode. Exploding results in a rather comical visual-effect, similar to when the player submerges in goo/oil, just as the player model disappears before the game-over screen. If the player successfully reduces their bloat via enough of the relevant consumables, their clothing is automatically re-equipped.

Expansion Derivations: Elemental damage, hazard zones and certain enemy attacks can trigger the various types of bloats. This can be via weapons equipped with status mods, or those attacks which are already designed to cause elemental damage. Hazard zones won’t cause bloat straight away, as these have a percentage counter which slowly builds. At 100%, the various stages of bloat will begin. The only exception to this rule is in the case of deadzones, where growth starts immediately. Yeah, that’s just how polluted these areas are. The reason for this is so the player isn’t required to start asphyxiating in order to cause the weight-gain effect off the bat, and are presumed to be already wearing the relevant suit.


You can write as many colorful paragraphs as you like, but as of right now, the only mods available for Biomutant are tweaks for the shaders, which are just edits to the external config files. Unless they release an API or similair, we’re not going to see much else for this game.


Thanks for the critique, it was actually super helpful in getting me to make an edit to the original. Stirring people along on a hopeless project is the last thing I wanted to do, and so I apologize in advance if that’s what it was made out to be. Other than that, it was good to shorten down the post to its most direct goals (with the focus being on the player).

However, I still reckon the current lack of an API isn’t the end of the world. I might not have the time and resources to undertake such a project myself, but I can continue to make edits/improvements as well as taking on feedback. I’m mainly setting out to start a discussion, as a mod like this would simply be sick to see some day (even if it takes a while for an API to be produced, we’ll see).

Still, I’m probs only gonna be seeing that as a bonus. Getting the idea written is enough for me.

this hound only says one thing
good luck
all things worth doing inevitably require effort

Biomutant has been made on unreal engine 4. Ingame body shape sliders just use bones scaling instead of shape keys. I don’t know what do you mean by API and other modification software, but the only software needed to mod Unreal engine 4 games is Unreal engine with the same version. The main problem is that you can’t import cooked parts of project to your own project and this make impossible to create a mod which change gameplay. You can only change assets. Since this game has failed miserably and is not popular I don’t think someone ever create some kind of additional API or software or unreal engine project which will be able to change gameplay.