I wouldn't open that box if I were you- you'll feel a pleasant tingling sensation, but your hair might fall out later. As a scientist, I can tell you this means there is a ghost in there with unfinished baldness-related business.

Radiants deal with radiation, although in a completely scientifically inaccurate manner. If your referee is running a game where radiation acts more realistically, they should at the very least strip out all mutation-related effects from this archetype and probably just disallow it completely. On the other hand, if your game is gonzo as fuck then a character taking levels in Radiant is going to fit right in.

Radiant Wield radiation.
caret-right Meltdown Taking damage irradiates your surroundings.
caret-right Nuclear Power Split the atom for resources.
caret-right Radgeneration Regenerate when radioactive.
caret-right Radioscan See inside things.
caret-right Wastelander Deal with environmental radiation.

Radiant
Offense plus-circleIsotope Flash: As an action, you may inflict the Irradiated condition on any subject within throwing range (0-10 meters).

minus-circleWeaponized: This ability suffers failure chances from cover, concealment, and size differences between yourself and your target just like weapon attacks do.

minus-circleSupplies: Roll a trigger die when inflicting the Irradiated condition this way. If the result is 1-3, then doing so costs 1 Supplies. You cannot use this ability if you have no Supplies remaining.
Offense plus-circleHot Ammo: You know how to enhance your weapons with radioactive material. Whenever you make any weapon attack and the trigger die is 10+, you inflict the Irradiated condition to your target in addition to all of that attack's normal effects (damage, conditions, etc).

minus-circleMonoelemental: Your weapon attacks can only inflict a single elemental condition on a 10+ at a time. If you have levels in multiple Elemental archetypes, you pick which condition your 10+ trigger die attacks inflict each time.
Condition Explanation
mass-driver Irradiated minus-circle Cannot restore lost Energy or Flesh by any means.

minus-circle When rolling to remove condition at the end of the round, lose 1 Energy if result is 1-4 and lose nothing if result is 5+. If no Energy remains, lose Flesh instead. Rolling to remove as an action during the round does not cause lost Energy regardless of trigger die result.

minus-circle When rolling to remove condition at the end of the round, gain a random mutation if result is 1 and do not mutate if result is 2+. Rolling to remove as an action during the round does not cause mutation regardless of trigger die result.
Sidebar: Mutations
Mutation chart entries are meant as general guidance for the referee, who can go into as much detail as they please in describing the new mutation's exact appearance and nature.

Roll a die when you mutate to see what happens to you. You will probably need to roll more after for more information. Mutation rolls are not trigger dice and thus cannot be affected via abilities that affect trigger die results such as Luckster.
Roll Mutation
1 Non-Viable. Something's changed in the mutant's biology that makes them non-viable for the adventuring life. Roll again:

1-4. Messy Death. Flesh sloughs off bone, blood vessels seal themselves off, major organs atrophy, or similar. The mutant dies.
5-8. Abomination. The mutant becomes a shrieking, unnatural mass of eyes/teeth/tentacles/whatever, no longer recognizable as themselves or even their original species. The process drives them mad and they slither off to dwell in darkness. Maybe they'll be a problem later if you let them get away!
9-12. Immediate Retirement. Bones turn rubbery, limbs fall off, or similar mutations that don't kill the subject but do prevent them from pursuing an adventuring lifestyle due to a non-functional body or needing constant medical treatments to stay alive. If a player character, the mutant may immediately retire and grant all the benefits of retirement.
2 Crippled. The mutant's body has been crippled and weakened by a wholly non-beneficial mutation. Roll up a random injury from the Injuries chart; the mutant now has that injury permanently. Injuries from mutation cannot be healed like normal injuries, but maybe they could be reversed via questing for a cure if the referee allows it.

1. Butterfingers
2. Concussion
3. Dizziness
4. Exhaustion
5. Eye Trauma
6. Hallucinations
7. Lameness
8. Noisy
9. Numbness
10. Parasites
11. Shakes
12. Vulnerability
3 Weakness. The new mutation has drawbacks but also carries certain benefits. Roll again to gain a new weakness (and gain new associated bonus abilities that you and the referee agree make sense) from the Weaknesses list. The mutant's physical appearance changes in some way to clearly show their new nature. If you randomly roll up a weakness you already have, you lose it (and its associated bonus abilities) instead.
4 Coloration. The mutant's coloration changes. This is a purely cosmetic mutation with no effect on game mechanics. Roll twice more: once for location and again for coloration.

1-4. Whole/Most of body
5-8. Hair/Fur/Feathers/Scales Only
9-10. Eyes
11-12. Single limb or body part of referee's choice

1. White
2. Black
3. Brown
4. Red
5. Orange
6. Yellow
7. Green
8. Blue
9. Purple
10. Grey
11. Transparent
12. Roll twice and combine
5 New Feature. The mutant grows a new body feature they didn't have before. This is a purely cosmetic mutation with no effect on game mechanics. Roll again to see what grows in. If the mutant already had the part in question, they grow an extra one or lose what they had (referee's choice).

1. Antennae (1-8 insectoid, 9-10 fleshy, 11-12 telescopic)
2. Beak (1-4 long and thin, 6-8 short and stubby, 9-12 wide and flat)
3. Beard
4. Horns (1-3 goatlike, 4-6 bisonlike, 7-9 antlers, 10-12 single unicornlike)
5. Crest on spine/head (1-4 fluffy, 5-8 leathery, 9-12 bony)
6. Hump (1-6 on back, 7-9 on stomach, 10-12 on random limb)
7. Fangs (1-6 generic, 7-9 sabre-tooth/walruslike, 10-12 boar/elephant tusks)
8. Fin (1-8 dorsal, 9-12 limbs)
9. Breasts
10. Pouch (1-8 on stomach, 9-12 on back)
11. Tail (1-2 stubby, 3-4 long/thin, 5-6 bushy, 7-8 prehensile, 9-10 mace tail, 11-12 scorpionesque)
12. Vestigial Wings (1-4 batlike, 5-8 feathered, 9-12 insectoid)
6 Texture. The mutant's skin or outer surfaces are changed in some way. This is a purely cosmetic mutation with no effect on game mechanics. Roll again to see how the skin is altered.

1-6. Whole body
7-12. Clumps/partial coverage

1. Fur
2. Bark
3. Scales
4. Feathers
5. Crystalline growths
6. Loose, wrinkled skin
7. Slimy/oozing skin
8. Barbs/quills
9. Leaves
10. Chitinous plates
11. Undulating cilia
12. Patterned coloration (referee's choice of spotted, striped, blotchy, etc)
7 Altered Head. One of the mutant's head/face parts is changed to a new form. This is a purely cosmetic mutation with no effect on game mechanics. Roll again to see what changes. If the mutant rolls something they already have, they lose it or gain another one (referee's choice).

1. Eyestalks (1-8 crustacean, 9-12 fleshy)
2. Pupil alteration (1-3 catlike, 4-6 goatlike, 7-9 cephalopodlike, 10-12 something really weird)
3. Compound eyes (1-8 normal size, 9-12 huge)
4. One eye (cyclops style)
5. Extra eye(s) (1-4 +1, 5-8 +2, 9-10 +4, 11-12 +6)
6. Tongue (1-4 normal but elongated, 5-8 snakelike/forked, 9-12 froglike/sticky)
7. Complex mouth (1-6 insectoid mandibles, 7-12 secondary mouth inside normal one)
8. Nose (1-3 insectoid proboscis, 4-6 bestial, 7-9 trunk, 10-12 noseless)
9. Hair (1-3 hairless, 4-6 leaves, 7-9 feathers, 10-12 tentacles)
10. Ears (1-6 perky animal ears, 7-9 floppy animal ears, 10-12 earless)
11. Neck (1-6 no neck, 7-12 elongated)
12. Picasso face (rearrange everything, referee's choice how)
8 Altered Limb. One of the mutant's appendages is changed to a new form. This is a purely cosmetic mutation with no effect on game mechanics. Roll again to see what changes. If the mutant rolls something they already have, they lose it or gain another one (referee's choice).

1-2. Single arm/hand (1-2 scaly talon, 3-4 crab claw, 5-6 tentacle, 7-8 mantis arm, 9-10 plant, 11-12 pawlike)
3-5. Both arms/hands (1-3 talons, 4-6 crab claws, 7-9 tentacles, 10-12 webbed digits)
6-7. Single leg/foot (1-4 hoof, 5-8 paw, 9-12 insectoid)
8-10. Both legs/feet (1-2 hooves, 3-4 paws, 5-6 replaced with snakelike tail, 7-8 fused into single powerful hopper, 9-10 bunch of crablike legs, 11-12 mass of tentacles)
11-12. Genitals (1-4 switch sex, 5-8 hermaphroditic, 9-10 neuter/sexless, 11-12 replaced with something both horrifying and confusing to behold)
9 Altered Size. The mutant is partially or completely changed in size. This is a purely cosmetic mutation with no effect on game mechanics except for results that change the mutant's overall size category. Roll again to see what changes.

1-4. Mutant grows 1 size category
5-8. Mutant shrinks 1 size category
9-10. Single part of body shrinks (1 single foot/leg, 2 both feet/legs, 3 single arm/hand, 4 both arms/hands, 5 stomach, 6 head, 7 eyes, 8 nose, 9 ears, 10 mouth, 11 one full side, 12 sex characteristics)
11-12. Single part of body grows (1 single foot/leg, 2 both feet/legs, 3 single arm/hand, 4 both arms/hands, 5 stomach, 6 head, 7 eyes, 8 nose, 9 ears, 10 mouth, 11 one full side, 12 sex characteristics)
10 Alteration. The mutant's body layout or function is radically altered in some way. This is a purely cosmetic mutation with no effect on game mechanics. Roll again to see what changes.

1. Mouths in appendages
2. Eyes in appendages
3. Headless (brain/facial features in torso)
4. Knuckle Walker (feet act as hands and vice versa)
5. Physically young/immature
6. Physically old
7. Reverse Pedalism (bipedal→ quadrupedal and vice versa, legless grow legs, many legs lose all and slither)
8. Walking Head (no torso, only big head with limbs directly attached)
9. Tremendously fat
10. Skeletal thin
11. Bioluminescence (shed no actual light but partial/whole body glows in the dark)
12. Sheds skin regularly
11 Beneficial Mutation. The mutation has some sort of beneficial effect for the mutant, giving them natural proficiency in a random archetype. Roll up/randomly select an archetype from those available in your campaign world, then come up with some sort of visually obvious mutation that would help the mutant use it. For example, the Lacerator archetype would be aided through growing sturdy claws and the Firebug archetype might be greatly aided through the excretion of flammable oil. The mutant can now permanently take levels in the specified archetype without having to use a keystone.
12 Perfect Mutation. As Beneficial Mutation (result of 11) but the mutant immediately and instantly levels up after mutating, gaining one new level in the archetype that their mutation benefits. This has no cost of time, XP, or keystone.

Meltdown
Offense plus-circleOutflow Exhaust: Your internal nuclear reactions are prone to eruption. Whenever you lose Energy for any reason, you can choose to immediately inflict the Irradiated condition to every creature within 2 meters of your position. If you lose Energy from sprinting or another ability that changes your position, Meltdown strikes everything within 2 meters of your final position.

plus-circlePripyat Sunrise: When you lose Flesh, choosing to use Meltdown causes every creature you inflicted the Irradiated condition on to also lose 1 point of Flesh. Note that this can provoke a struck target who also knows the Meltdown ability to have a meltdown of their own and trigger a runaway chain reaction that doesn't stop until one of you decides to chicken out.

plus-circleParting Gift: If you are killed, the dungeon node you were in is flooded with environmental radiation until the end of the current session.

Nuclear Power
Utility plus-circleFree Energy: As an action, you may create a nuclear reaction which provides you with abundant resources. You immediately gain 1-4 nuclear resources which can be spent in place of any other resource (Provisions, Supplies, Mojo). Every time you use this ability, roll a die to determine exactly how many nuclear resources are created: 1-3 means 1, 4-6 means 2, 7-9 means 3, and 10+ means 4. This die isn't a trigger die and cannot be manipulated by effects that alter trigger dice.

minus-circleDissipation: Resources gained from this ability are short-lived. Any nuclear resources that you don't spend disappear at the end of the current exploration turn and are wasted.

minus-circleNo Cash Substitute: You can only use nuclear resources to pay costs incurred from ability use. You can't use them to feed yourself, mitigate Stress, relight snuffed lights, or similar.

minus-circleReagent Costs: Creating nuclear resources cannot be done from nothing. Using this ability costs 1 Supplies. You cannot use nuclear resources from a previous use of Nuclear Power to pay this cost.

Radgeneration
Protection plus-circleAtomic Heart: You find radiation invigorating. Every time you start your turn with the Irradiated condition, you automatically heal up to 2 points of lost Energy. If you have radiation sickness from environmental exposure, you heal 2 Energy once per exploration turn. This healing is an exception to the normal rule that you cannot heal by any means when irradiated.

plus-circleAcclimatized: You never lose Energy/Flesh from the Irradiated condition or to radiation sickness.

plus-circleI'm Sorry, Jon: When you mutate as a result of radiation exposure, you immediately regain all lost Flesh, Energy, and Attention. You can choose to mutate when your recovery die result is a 2 or 3 (getting a 1 means you are forced to mutate as normal).

minus-circleOther Penalties: The non-damaging effects of the Irradiated condition still apply to you. You cannot heal lost Energy or Flesh via any means other than through Radgeneration, and you still run the risk of disadvantageous mutations.

Radioscan
Utility plus-circleX-Ray Vision: By spending a procedure of work, you can examine the internal structure of a creature or object that's no larger than size 5 (approximately the size of a human). This reveals all irregularities, hidden mutations, embedded objects, ingested poisons, parasites, objects hidden via the Duplicity ability from the Thief archetype, and everything else relevant and/or interesting.

minus-circleNo Moving Subjects: When using Radioscan on a creature they must hold still for the duration, meaning they must be restrained or willing.

minus-circleTelemetrist's Burden: Roll a trigger die when radioscanning something. If the result is 1-3, then doing so costs 1 Supplies. If you have no Supplies remaining, you cannot radioscan anything.
Utility plus-circleRadiodating: You can determine the exact age of any material. “Age” for organic material tells you the time when it was last alive, inorganic material tells you the time when it was formed.
Utility plus-circleFind Hidden: Every time you're involved in an operation challenge with hidden dice, one hidden die is automatically revealed at the beginning of the challenge simply because you're there. This effect somehow even works on challenges that have nothing to do with studying the internal structure of physical things, such as winning arguments.

Wastelander
Utility plus-circleGeiger Counter: You can clearly sense the exact borders of any environmental radiation you encounter, and can tell the difference between normal and extreme environmental radiation areas.
Protection plus-circleRad-X: You can remove radiation sickness or the Irradiated condition from yourself or an adjacent ally as an action. This ability even allows you to remove radiation sickness while still inside an area of environmental radiation, which is normally impossible.

plus-circlePurge: You can also us this ability to cleanse an irradiated object, allowing you to carry it in your inventory safely.

minus-circleProvisions: Removing radiation sickness or the Irradiated condition from a target or purging an object of residual radiation costs 1 Provisions.
Sidebar: Environmental Radiation and Radiation Sickness
Some adventure locations might have an elevated level of environmental radiation, such as ancient reactors or fresh bomb craters. The exact boundaries of these areas are invisible to any creature without the Wastelander ability. Every time an exploration turn is completed inside an area of environmental radiation, roll a trigger die for every creature (the referee might choose to do this in secret). If the result is a 1-3, that creature comes down with radiation sickness.

Radiation sickness is nearly identical to the Irradiated condition (including the inability of its sufferers to heal lost Energy/Flesh), but lasts longer and acts more slowly. Radiation sickness can only be recovered from by making recovery rolls at the end of each exploration turn instead of at the end of each combat round. Negative effects from low trigger die results on this recovery check (loss of Energy/Flesh, mutation) apply exactly the same as recovery trigger die results for the Irradiated condition. When still actively inside an area of environmental radiation, radiation sickness cannot be recovered from regardless of the recovery die result, but recovery checks are still made and negative effects still accrue.

Areas of environmental radiation sometimes have more extreme levels of radiation towards their centers. Extreme environmental radiation areas act exactly the same, but inflict radiation sickness automatically instead of rolling for it.

Objects exposed to radiation over a long period of time might become irradiated at the referee's discretion. If you have an irradiated object in your inventory, you act as if you are inside an area of environmental radiation for as long as you carry it.