Gaming Guide

ARC Raiders: How to Farm Fossilized Lightning During an Electromagnetic Storm

Two Electromagnetic Storm routes, a Blue Gate ridge loop and a late-raid extract camp, for Amplified weapon upgrades.

Two Electromagnetic Storm routes, a Blue Gate ridge loop and a late-raid extract camp, for Amplified weapon upgrades.

Image: Embark Studios

Fossilized Lightning gates every Amplified weapon perk in ARC Raiders, and it only exists while an Electromagnetic Storm is battering the map. Each piece is left behind by a single bolt of lightning, so the farm is about getting as many bolts as possible to land near you. A two-player squad running a tight loop on The Blue Gate can pull 15 to 20 pieces combined in one match.

Quick answer: Queue The Blue Gate with Electromagnetic Storm active, loop the ridge between Maintenance Bunker and Broken Earth, grab every glowing node where lightning lands, then extract at Overlook Airshaft.


Fossilized Lightning and Amplified weapon upgrades

Fossilized Lightning is an Epic item in the Nature category. Amplified weapons use it to unlock their perks. Incendiary Rounds on the Rattler, Incendiary Grenades on the Hullcracker, and X-Rounds on the Anvil all draw on it. Each upgrade node on the Amplified Hullcracker, Anvil, Rattler, Aphelion and Canto costs 3 Fossilized Lightning.

The cost does not stop at the first craft. If you die and lose an upgraded weapon, the perk goes with it, and the replacement needs another 3 pieces for the same node. Players who run Amplified gear in risky raids end up needing a steady supply, not a one-off stash.

Every amplifiable weapon has its own set of upgrades. These are the base weapons that have Amplified variants and the upgrades each one can take.

WeaponCategoryWeightAmplification upgrades
Hullcracker (Epic)Special7Incendiary Grenades, Mag Reload
AphelionBattle Rifle10Bigger Mag, Charged Burst, Incendiary Rounds, Increased Burst
Rattler (Common)Assault Rifle6Drum Mag, Incendiary Rounds, More Reload
Bettina (Epic)Assault Rifle11Bigger Mag, Semi-Auto, X-Rounds
Burletta (Uncommon)Pistol4Burst Fire, Full-Auto, Increased Burst, Sprint Shooting
Renegade (Rare)Battle Rifle10More Reload, Scoped

The Amplified Aphelion retains the base rifle’s four upgrade options and weighs 10. It launches fast-moving energy ammunition in a 2-Round Burst, with Strong ARC armor penetration.

The Amplified Rattler is the least expensive way to enter the system. The base model is a Common assault rifle, and it reloads two bullets per action. Its magazine capacity rises from 12 at Level I to 16, then 20, and reaches 24 at Level IV.


How Electromagnetic Storm lightning spawns Fossilized Lightning

Lightning appears to strike at random, but both farming routes rely on a few rules that hold every time.

Electromagnetic Storm
Electromagnetic Storm. Image: Embark Studios
  • Bolts only fall while the Electromagnetic Storm condition is active. With no storm, no lightning nodes can spawn.
  • A piece appears exactly where a bolt hits the ground. It is a glowing, molten-looking crystal that you can pick up straight into your inventory.
  • Not every strike leaves one. Some bolts leave only a scorch mark.
  • Strikes target areas where players are standing. They hit more often around each survivor as the lobby empties and the timer runs down.
  • Worn backpacks in buildings and out in the open can also contain Fossilized Lightning.
  • Pieces do not stack. Each one takes up its own backpack slot.

The storm also changes the raid itself. Fewer Return Points are active, and lightning fries electronics and disrupts ARC machines. You only get a short window to farm, because the storm runs in roughly hour-long blocks a few times a day. Check the event list before you queue.

Raiders can be hit by lightning as well. A direct hit causes severe damage and leaves you stunned; jumping won’t protect you, so stay near cover while collecting pickups.


The Blue Gate loop: Maintenance Bunker to Broken Earth

This route produces the most Fossilized Lightning per match. Players run back and forth across the boundary between two named areas instead of standing still. The working theory is that crossing between neighboring sub-zones resets the timer on nearby strikes, which keeps bolts landing around you. A duo finished one run holding 7 and 8 pieces each, with more collected along the way.

The Blue Gate
The Blue Gate. Image: Embark Studios
Open the event selection and choose The Blue Gate while the Electromagnetic Storm condition is running. The event card lists the storm’s effects, including fewer active Return Points and lightning strikes.
Event Selection01:05Event Selection
Confirm The Blue Gate with the Electromagnetic Storm condition active before you queue. Shown at 01:05 in Arekkz Gaming’s video. Image: Embark Studios
Head for the central part of the map where Maintenance Bunker and Broken Earth meet. Mark the stretch of ridge that links the two areas so your squad runs the same line.
Map Route Demonstration02:00Map Route Demonstration
The farm runs through the middle of The Blue Gate, between Maintenance Bunker and Broken Earth. Shown at 02:00 in Arekkz Gaming’s video. Image: Embark Studios
Patrol the ridge by Maintenance Bunker and keep crossing into Broken Earth and back. Do not stay in one spot, because the movement between the two areas is what keeps strikes coming.
Patrolling the Ridge03:08Patrolling the Ridge
Running the ridge beside Maintenance Bunker, the main stretch of the loop. Shown at 03:08 in Arekkz Gaming’s video. Image: Embark Studios
Listen for thunder and watch for flashes nearby, then run straight to the impact point. The ridge and cliff edge often take several strikes in a row, so call them out to your teammate as they land.
Additional Fossilized Lightning Spawns04:05Additional Fossilized Lightning Spawns
A fresh strike on the ridge. Go to the impact point right away to check for a node. Shown at 04:05 in Arekkz Gaming’s video. Image: Embark Studios
Interact with the glowing node at the impact point to pick up the Fossilized Lightning. Keep a free slot ready, because each piece needs its own slot.
Another Spawn Collected03:22Another Spawn Collected
A Fossilized Lightning node left by a strike, ready to collect. Shown at 03:22 in Arekkz Gaming’s video. Image: Embark Studios
Keep an eye on the extraction timer and move to Overlook Airshaft before it closes. Strikes keep landing near the end, and one more node can drop right beside the extraction elevator.

Stay out of the south-west corner around Highway Collapse and Adorned Wreckage. Time spent there during the storm produced no Fossilized Lightning at all.

Comet Igniters on the same ridge

Flying Comet ARC drones pass over the Maintenance Bunker ridge throughout the loop, so you can farm them without leaving the route. The Hullcracker handles them well. It is an Epic Special weapon whose explosive shots only go off when they hit ARC, and it can drop a Comet in one or two hits. ARC Turbines can also turn up nearby during the storm.

Comet Igniter Farming04:14Comet Igniter Farming
Taking down a flying Comet with the Hullcracker between lightning pickups. Shown at 04:14 in Arekkz Gaming’s video. Image: Embark Studios

The Amplified Hullcracker uses the same Incendiary Grenades and Mag Reload upgrades as the base weapon and weighs 7. Its Incendiary Grenades perk sets fire when a round detonates on ARC, and it is one of the upgrades that costs Fossilized Lightning.

Comets drop Comet Igniters. Igniters go into the Extended Burst Cycles, Deadline Blueprint and Explosive Mine Blueprint recipes, and you can also throw one as an explosive.

Comet IgniterValue
RarityRare
CategoryRecyclable
Loot categoryARC
Item weight1
Max stack3

A stack holds three, so one slot covers three Comet kills before Igniters start taking space away from Fossilized Lightning.


Last-extract camp method on any storm map

If you are not on The Blue Gate, use the rule that strikes cluster around the last players left. Hold the final open extraction point for the closing minutes of the raid and the storm will keep hitting the ground around you. The Red Lakes Balcony Lift on Dam Battlegrounds works well because it sits on open rooftop ground. Expect around six pieces from a typical run and up to eight from a good one.

Topographic Destinations map with labeled locations and rounds played counters such as 6/25 for Pendola Pass.
The Destinations map lists Pendola Pass, Spaceport, Stella Montis, The Blue Gate, Riven Tides, Buried City, Dam Battlegrounds, ARC Frigate and the Practice Range, with rounds played shown on the locked ones.
Enter any raid while Electromagnetic Storm is the active condition. If it isn’t underway, leave and queue for another raid.
On the way across the map, open any worn backpacks you pass. They can contain Fossilized Lightning, which adds to whatever the storm gives you later.
Work out which extraction point will stay open longest and move toward it. Other lifts will warn you as they close, such as a 90-second notice for the Central Swamp Lift.
Stay near that extract, with cover close at hand, for roughly the last five minutes. While waiting, fight any ARC that passes or work on a task such as Solid-Core Casting Tech, which requires destroying 50 Flying ARC with shotguns.
In the last minutes, sweep the rooftop and the area around the elevator and collect every node the strikes have left. Make sure you have free slots, because none of the pieces stack.
Board the lift before it closes. Anything you are carrying is lost if the extraction shuts with you still outside.

Confirming the haul and spending it

Fossilized Lightning picked up during a raid only counts once you extract. You can tell the run worked when you are back in Speranza and the pieces are still in your backpack. Either method can be checked mid-raid by opening your inventory and counting the stacks of one, since each piece shows up in its own slot.

Inventory menu with stash grid on the left, empty loadout slots on the right and a context menu for Hornet Driver.
The Inventory screen shows the Stash with a right-click menu on the Hornet Driver offering Equip, Move to Backpack, Move to Safe Pocket, Inspect, Sell and Recycle.

Once the pieces are home, you have three options. Spend them in sets of three on Amplified perks. Sell them for Coins. Or recycle them into Explosive Compound, which skips the slower Crude Explosives and Oil route to that material. If you run Amplified weapons often, keep at least three in reserve so you can rebuild your main perk the next time a raid goes badly.