Chimera Mutations are adaptations of the Chimera Parasite in response to the threat REACT poses to its existence. A total of seven mutations are currently known. On higher difficulties, one will randomly appear throughout an Incursion, creating ever more dangerous situations and causing players to rethink their strategies.
Armored Nests are Nests that have developed an extra-resilient outer covering. These Armored Nests are protected by a dried goo-carapace and make them highly resistant to ballistic damage.
Armored Nests can still be destroyed with a Takedown but will otherwise be highly resistant to damage from gunfire and regular melee attacks. The armored encasing will briefly retract as it spawns an enemy, giving players an opportunity to destroy them. Alternatively, explosives can be used to destroy Armored Nests immediately.
Blinding Spore Carriers
Blinding Spore Carriers are low tier enemies, typically Grunts and Spikers, that have Blinding Spores growing out of them. These enemies will rush players, causing Spores to attach and detonate. With precise shots the Spores can also be removed from the carrier. When the Carrier dies the Spores will also be destroyed without releasing their toxic cloud.
Cloaked Archæans are enemies made nearly invisible without the need of a Lurker. They will remain cloaked unless they are alerted or take damage. This can potentially cause unsuspecting players to alert all enemies within an area. Despite this, they can still be detected with Scan Mines, Scan Grenades, or the Recon Vapor Device.
Caustic Sprawl is Sprawl that has mutated to secrete a cocktail of extremely corrosive chemicals. Recognizable by it green hue, it will slow down player movement while boosting enemy movement. Unlike normal Sprawl, extended contact with it will deal damage to a player every three seconds. It can be removed with gunfire, melee hits, abilities, explosives, and the REACT Laser. Sprawl left behind by killed enemies will also leave Caustic Sprawl while the mutation is active.
Sprawl Overflow causes all enemies to leave behind Sprawl as they move. This will significantly reduce player movement in a subzone and increase enemy capabilities.
Spontaneous Sludge causes the remains of Archæans who have not been killed through weak points to turn into Sludge. As with normal Sludge, it will move towards any disturbance when alerted and stab at the threat with extendable tendrils, they can also fraction and recombine almost indefinitely unless destroyed. Sludge can quickly overwhelm players if they are not careful to target enemy weak points.
Chimera Fog is gaseous thick fog produced by Sprawl cell colonies. As a result, player visibility is greatly reduced to three meters while enemy visibility remains unaffected. Chimera Fog cannot be removed and will be present for the entire duration the player is within a subzone. Players should traverse subzones with caution and utilize recon devices to scout out areas.
Revived Archæans are enemies that can revive themselves if not eliminated by their weak point or by a Takedown. When the Archæan gets knocked down, players have a moment to neutralize it by attacking it at it's weak point to obliterate it. Revived Archæans can easily overwhelm players on higher difficulties with an Apex in the area if they are not careful to target enemy weak points.
Spontaneous Blinding Mines
Spontaneous Blinding Mines causes the remains of Archæans who have not been killed through weak points to turn into Blinding Mines. As with regular Blinding Mines that are set by the Sower, should a player get too close to a mine, it will detonate and will temporary blind the player for a few seconds. The mines themselves take about a second to detonate, so that gives the player some time to dispose of it.
Spontaneous Exploding Mines
Spontaneous Exploding Mines causes the remains of Archæans who have not been killed through weak points to turn into Exploding Mines. Exploding Mines are a new variant that should a player get too close, it can damage and temporarily immobilize the player for a few seconds, similar to the attack from the Rooter upon detonation. The mines themselves take about a second to detonate, so that gives the player some time to dispose of it.
Archæan Havoc causes Archæans to become stronger when attempting to breach through areas, allowing them to break through barricades, reinforced walls, and containment doors instantly, effectively making fortifying an area useless.
Immortal Smasher have no weakness to them as their body are completely covered in hardened carapace. They can not be damaged or eliminated by a Takedown. Players are advised to completely avoid engaging with an Immortal Smasher or to divert it with gadgets and abilities.