Effects
Effects are certain conditions and modifiers that impact gameplay in various ways. These effects are viewable on the Galactic Map. The number of Effects and type vary by Biome, Faction, and Difficulty.
Weapons Experimentation/Arsenal Augmentation
Occasionally, Super Earth High Command makes certain Stratagems available for Helldivers to deploy with as an additional mission standard-issue stratagem. These augmentations are purely additive and do not take up a slot on a Helldiver's Stratagem loadout.
Democracy Space Station
The Democracy Space Station can provide a Helldiver-funded "Tactical Action" in addition to the Liberation Campaign boosting "Operational Support" to whichever planet is being orbited.
- Operational Support - The presence of the DSS near this planet provides a slight boost to Liberation Campaign progress and a 35% percent reduction of the cooldown of mechs.
- Eagle Storm - Deploys periodic Eagle Strafing Runs during missions. Enemy progress in Defense Campaigns is slowed.
- Orbital Blockade - Defense Campaigns cannot originate from this planet. The Hellpod Space Optimization Booster is automatically active for all missions.
- Heavy Ordinance Distribution - Gives access to the Orbital 380mm HE Barrage stratagem during missions. Accelerates progress in Liberation Campaigns.
Environmental Conditions
Environmental conditions refer to geophysical events that influence a Planet's environment, experienced throughout missions.
Acid Storms – Corrosive acid storms temporarily reduce armor effectiveness for both enemy and friendly units.
Blizzards – Intense blizzards reduce mobility and moderately reduce visibility for both enemy and friendly units.
Extreme Cold – Periods of freezing temperatures reduce rate of fire and delay heat buildup in weapons.
Fire Tornados – Planet is ravaged by deadly fire tornados.
Intense Heat – Periods of high temperatures increase stamina drain and speed up heat buildup in weapons.
Ion Storms – Ion storms intermittently disable Stratagems.
Meteor Storms – Meteors impact the surface causing massive damage.
Rainstorms – Torrential rainstorms reduce visibility.
Sandstorms – Dense sandstorms reduce mobility and greatly reduce visibility for both enemy and friendly units.
Thick Fog – Dense fog lightly reduces visibility for both enemy and friendly units.
Tremors – Frequent earthquakes stun players and enemies alike.
Volcanic Activity – Volcanos throw burning rocks around this planet.
Heavy Gloom Shroud This planet is completely engulfed by the Gloom, severely impeding logistical support. Extraction times are increased by 40 seconds, Eagle Re-arm time is increased by 30% and Ammo from pickups is reduced by 50%.- Gloom Source: This planet continually produces a thick atmospheric Gloom cover, rendering logistical support extremely challenging. Total Reinforcements are reduced by 20%, Eagle Re-arm time is increased by 30%, and Ammo from pickups is reduced by 50%.
Operational Effects
Sometimes, during certain events or Major Orders, some, if not all planets may gain an extra effect/modifier, available on all difficulties.
- Orbital Fluctuations: All Orbital Stratagems have an increased cooldown. (not to be confused with the Operation Modifier with the same name, this effect only affects Orbital Stratagems)
- Medical Supply Strain: Number of stims each Helldiver deploys with decreased by 1.
- Pilot Shortage: Extraction takes 30 additional seconds.
- Slower Eagle Rearm: Eagle Rearm time is 25% slower.
Operation Modifiers
Operation Modifiers are added obstacles that Helldivers must handle on the battlefield. A single Modifier will appear on 
Hard, increasing to two at 
Impossible. Operation Modifiers do not appear on planets undergoing a Defense Campaign.
General
- Complex Stratagem Plotting – Stratagem Call-in time increased by 50%.
- Orbital Fluctuations – Stratagem cooldown increased by 25%.
- Poor Intel – Objective locations are hidden.
- Civilians and SEAF in Area - SEAF Soldier squads and Civilians are both on the battlefield. (Event modifier only present in Metropolis Biomes)
Faction-Specific
- Atmospheric Spores – Map obscured by Bug Spores.
- Roving Shriekers - Flying Shrieker swarms traverse the battlefield.
- Gunship Patrols - Flying Gunships patrol the battlefield.
- Leviathan Blockade - Flying Leviathan warships patrol the battlefield.
Removed
- AA Defenses – Stratagem slots reduced by 1.
- Atmospheric Interference – Orbital Stratagems Scatter Increased.
- Electronic Countermeasures – Stratagem Codes Scrambled.
Enemy Forces
Some planets or cities will have modifiers that effect the types of enemy units that spawn, with them either increasing the frequency of specific units, replacing certain units with unique variants or having entirely unique units.
- Predator Strain - Unique cunning variants of Hunters and Stalkers will appear.
- Rupture Strain - Unique burrowing variants of Warriors, Spewers and Chargers will appear.
- Spore Burst Strain - Unique explosive variants of Scavengers, Hunters and Warriors will appear.
- Dragonroaches - Bile Titans will be replaced with a unique flying enemy; the Dragonroach.
- Hive Lords - The colossal worm-like Hive Lord will appear. (Requires
Suicide Mission or above.)
- Jet Brigade - Unique Assault Raider units will appear alongside jetpack-equipped variants of Troopers, MG Raiders, Commissars, Devastators, Scorcher and Bruiser Hulks.
- Incineration Corps - Unique Confligration Devastator and Hulk Firebomber units will appear alongside incendiary-wielding variants of Troopers, Rocket Raiders and Heavy Devastators.
- Cyborgs - Unique cyborg Agitator, Radical and Vox Engine units will appear.
- Hulk surge - Hulk units will spawn with increased frequency.
- Heavy Armor Surge - Tanks and Striders will spawn with increased frequency.
- Devastator Surge - Devastator units will spawn with increased frequency.
Other Effects
Armor Passives
Armor passives are unique abilities or enhancements in Helldivers 2, each tied to its corresponding body armors.
Boosters
Each Helldiver has the option to add a booster before deployment, buffing the entire squad.
Physical Conditions
Physical conditions refer to adverse effects experienced on the battlefield.