Status effects
Status effects are temporary, usually negative, character modifications resulting from the character's interactions with the game, such as poisoning after getting hit by a radscorpion, or addiction after consuming a drug.
For a list of effects associated with critical hits, see critical effects.
Irradiation
| Severity | Penalty |
|---|---|
| 5% | -10 healing rate |
| 10% | -5 Sequence |
| 15% | -1 Charisma |
| 20% | -1 Endurance |
| 25% | -1 Agility |
| 30% | -1 Perception |
| 35% | -1 Strength |
| 40% | -10% critical chance |
| 45% | -1 to all SPECIAL attributes |
| 50% | -3% to all damage resistances |
| 55% | -3 to all damage thresholds |
| 60% | -2% to all damage resistances (stacks for a total of -5%) |
| 65% | -1 to all SPECIAL attributes (stacks for a total of -2) |
| 70% | Maximum hit points reduced by at least 25% |
| 75% | Critical chance set to 1% |
| 80% | Healing rate set to 0 |
| 85% | Action points reduced by at least 50% |
| 90% | -1 to all SPECIAL attributes (stacks for a total of -3) |
| 95% | All damage resistances set to 0 |
| 100% | Hit points set to 1 |
Irradiation means radiation exposure.
Radioactive contamination builds up over time as you visit places with intense background radiation (such as the Glow or the Lost Hill bunker), get hit by attacks that expose you to radioactive particles (ELECTRO-RAD Rockets, Rad Shot, Aliens), or ingest radioactive substances. A status indicator will appear in the top‑left corner of the screen once there's enough radiation in you that it starts affecting your stats; mouse over it for details.
Any character can instantly become fully shielded from all radiation by equipping a suit of TMA Metal Armor. Failing that, the effects of radiation exposure can be mitigated by increasing your radiation resistance.
Radiation resistance reduces the dose of radiation you receive upon exposure by a percentage. It is governed by Endurance, which grants +2% radiation resistance per point (or 1% if you have Fast Metabolism).
Rad Resistance and Snakeater support perks grant 30% and 20% of radiation resistance respectively.
Rad-X grants +50% radiation resistance and increases its cap by 10%, allowing the stat to reach 100% (full immunity) but note that some types of radiation (such as that you get exposed to in the Lost Hill bunker) will penetrate a portion of your radiation resistance.
Characters overexposed to radiation suffer radiation sickness which leads to escalating penalties as radiation exposure continues.
The severity of your radiation sickness is displayed as a percentage when you mouse over the dosimeter badge that says "Radiated" in the top‑left corner of the screen. The sickness has twenty stages, as shown in the table to the left.
Radiation continues to build up until it reaches 111% but there are no additional effects associated with going past 100%.
Taking RadAway will reduce your current radiation level by 50%.
Radiation can be purged instantly by doctor NPCs who can be found in most major locations.
Weakness
Weakness is a stacking debuff that subtracts 1% from one of the main six damage resistances in a fixed loop: normal → laser → fire → plasma → electrical → explosive.
| Weakness penalty breakdown | |||||||||||||||||||||||||||||||||||||||||||||||||||||||
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The table below is designed to help you quickly calculate your resistance penalties based on your Weakness stack count.
Here's a step-by-step explanation of how to use the table:
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The following items interact with the Weakness mechanic:
- Med-Tec Antidote instantly removes all Weakness stacks
- Perception grants +1% chance to resist Weakness per point
- Electrical damage applies
20 - target's PerceptionWeakness stacks on the target - Critical hits have a chance to apply Weakness to the target (ranged attacks aimed at arms only)
- More Critical Damage (weapon perk) allows your crits to apply additional Weakness stacks on your target
- Heresy Shot (Alien-exclusive weapon perk) applies 3 Weakness stacks on hit
- Leader (class perk) applies 2 Weakness stacks on NPCs with every hit
- Random Boy (class perk) has a chance to apply 50 Weakness stacks on the target when attacking without a combat timer
- Good Natured (trait) applies Weakness stacks to the character that has it when it kills an NPC
Addiction
Addicted characters suffer stat penalties when they're not under the effect of the drugs they're addicted to. Each drug has a unique addiction effect; see Drugs for details.
Characters with the Chem Reliant trait become addicted to the drugs they take automatically; everyone else is safe. To get rid of an addiction, you need to take a dose of Drug Antidote or reroll your character.
Poisoning
Poison stacks deal base damage equal to 2% of your max HP when they expire. If you reach 100 Poison stacks, they will expire all at once, dealing massive damage. Poison resistance allows you to negate a percentage of that damage. Radscorpions, Floaters, and Centaurs apply Poison stacks on hit. The Toxic Caves dungeon north of Klamath periodically applies Poison stacks to any player character inside. Taking poison damage immediately kills any character at or below 0 hit points.
The following items interact with the Poison mechanic:
- Endurance grants +5% poison resistance per point
- Regulators (class perk) with Fast Metabolism (trait) receive only +2.5% poison resistance per point of Endurance
- Luck grants +4% chance to avoid receiving poison stacks from NPC attacks per point
- Snakeater (support perk) grants +30% poison resistance
- Rad Resistance (support perk) grants +20% poison resistance
- Antidote (drug) removes 25 Poison stacks from a character
- Med-Tec Antidote (drug) removes all Poison stacks from a character
- ULT (T1 WE stat) grants +25% poison resistance
- S.ULT (T2 WE stat) grants +25% poison resistance
- Poison reduces healing received by 50% (or by 20% if you have the Vitality perk synergy)
- Random Boy (class perk)'s Strike has a chance to apply 50 Poison stacks to the target
- Random Boy has a chance to gain 50% poison resistance (lucky roll) or lose 25% poison resistance (unlucky roll)
- Eyebot (Robot transformation)'s favorite weapon type (Damage Knives) allows it to apply Poison stacks on hit
- Atomic Savant (level perk) allows normal DR to reduce damage taken from poison
- Survivalist (armor perk) increases your poison resistance cap by 10% and boosts your poison resistance by up to 60% (or 150% for Hubologist)
- Poisonous (weapon perk) applies up to 70 Poison stacks on the target (or up to 80 for Hubologist)
- Butcher (legendary weapon perk) allows lifesteal to work on poisoned NPCs
- Rad Shot (Alien-exclusive weapon perk, rank A) applies Poison on hit
Taunt
Taunt makes its targets unable to damage any characters other than the taunter. If the character that taunted you dies, the Taunt effect is immediately removed.
- Deathclaw (class perk)'s Rage taunts every hostile/neutral target on the map for 3 seconds
- Soldier (class perk)'s Strike applies Taunt to the target for 8 seconds
- Baiter (level perk) grants full immunity to taunts, and allows you to taunt all enemies within 30 hexes by using the Traps skill on yourself once every 2 minutes
- Coolheaded (level perk) lets you recover from being taunted 30% faster than normal
- Critical hits have a chance to apply Taunt to the target for 5 seconds
Injury
Injured characters suffer significant stat penalties related to the affected body part(s); see the table below.
| Injury | Penalty |
|---|---|
Crippled eyes |
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Crippled left/right arm |
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Crippled left/right leg |
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- The Doctor skill allows you to heal crippled limbs
- Leg injury is a common outcome of walking into a bear trap
- Frag Mines set by characters with the Architect perk synergy always cripple their victims' legs
- Explosive damage grants a chance to cripple limbs; the game rolls a random number between 75 and 250, and if it's lower than the damage dealt by the attack, a random injury is applied to the target
- Critical hits have a chance to cripple the body part that the attack targeted
- Iron Limbs (level perk) grants +8% resistance to crippled limbs (critical effect only)
- Deathclaw (class perk) receives a random injury when its Rage effect activates
Fury and Rage
Fury stacks accumulate as a character gets hit and dissipate as it hits others. When the Fury cap is reached, the stacks are consumed to trigger the Rage effect.
The effects of Fury and Rage vary by class. Some classes, such as Combat Master, benefit greatly from both; others, such as Paramedic, are heavily penalized.
Many classes don't have any defined effects associated with the mechanic; those that do can be found in the table below:
| Class | Fury cap | Fury effect (per stack) | Rage effect (triggers when Fury cap is reached) |
|---|---|---|---|
| Alien | 25 | -1% damage protection | Gain 400% of the regular amount of weapon XP for 10 seconds |
| Chosen One | 25 | -1 Charisma | Set 2 random SPECIAL attributes to 1 for 20 seconds |
| Combat Master | 25 | +6% critical power | Ignore your targets' critical resistances for 10 seconds |
| Cyborg | 25 | +2% EMP damage resistance | Surround yourself with EMP explosions that deal 25% of your max HP for 10 seconds |
| Deathclaw | 25 | +5 melee damage | Receive a random injury and taunt everyone on the map except your faction for 3 seconds |
| Infantry | 25 |
|
Gain +40% DT and DR penetration protection for 10 seconds |
| Killer | 10 | -2% DR (PvP only) | Set attack delay to 700 ms for 10 seconds |
| Paramedic | 25 | -0.5% movement speed | Lose the ability to run for 10 seconds |
| Priest | 25 | -10% radiation resistance | Create a 20-hex healing aura that restores 10% of your teammates' max HP per second for 10 seconds |
| Raider | 25 | -3 action points | Gain 100% Lifesteal for 10 seconds |
| Random Boy | 25 | -1 to all damage thresholds | Lose your current random stat rolls and gain the ability to reroll immediately |
| Robot (Sentry) | 25 | +2 to all damage thresholds | Paralyze all enemies within 10 hexes |
| Soldier | 10 | +1% chance to suffer Paralysis every time you take action |
Lose the ability to use healing items or skills for 10 seconds |
| Super Mutant | 15 | +2% damage protection (PvP only) | Lose all damage protection and gain +500% damage for 10 seconds |

