The Twins fight mainly consists of 2 types of enemies, the Bosses/Twins themselves and the enemy waves (elites, melee enemies and specials).
This guide aims to provide a team composition for killing the waves to help your team focus the bosses, as well as some extra tips.

Your team composition and roles will mainly consist of:

Wave Killing
Psyker with Smite, Psykinetic's Aura, Seer's Presence, Venting Shriek, Becalming Eruption, Creeping Flames, Solidity, Empowered Psionics
The wave killing Psyker's main role is:

• Using Smite to stun enemies, allowing the team to kill them
  
• Killing any enemies left over
  
• Clearing Rodin's mines so the team can dodge freely

Veteran with Plasma Gun, Krak Grenade, Survivalist, Field Improvisation, Demolition Stockpile, Voice of Command (with both ability modifiers), Rending Strikes, Focus Target
The wave killing Veteran's main roles is:

• Kill waves with Plasma gun, prioritising Ragers, Crushers, Maulers, and Shotgunners
  
• Cleaning up any other enemies left
  
• Placing Ammo Crate for grenade replenishment

Boss Management
Ogryn with Frag Bomb, Loyal Protector, Attention Seeker, Bruiser
The boss management Ogryn's main roles is:

• Taunt Rinda (Melee Twin), keeping them off the rest of the team
  
• Use Frag Bomb if team is getting overwhelmed, restocking from Ammo Crate

Assistance
The 4th team mate can be any class with a stun or crowd control ability that can assist team mates quickly, and weapons to help kill the bosses.
Examples are:
Ogryn with Indomitable (Bull Rush) or Point Blank Barrage
Veteran with Shredder or Krak Grenades, Field Improvisation, Voice of Command
Zealot with Stunstorm or Immolation Greandes, Chorus of Spiritual Fortitude

The following elite waves can spawn during the fight, spawning every 20 to 28 seconds.

• 2-3 Scab Shotgunners and 8-9 Scab Stalkers
  
• 2-3 Scab Maulers and 8-9 Scab Bruisers
  
• 2-3 Scab Ragers and 8-9 Scab Bruisers
  
• 1-2 Ogryn Crushers and 8-9 Scab Brusiers

Waves spawn from either the "East" or "West" of the arena.
A wave will spawn 5 seconds after the beginning of the fight.

The wave killing Psyker needs to keep an active watch for when these waves spawn, especially the ranged wave of Shotgunners and Stalkers, as they can start immediately dealing damage to team mates.

TO BE CONFIRMED: Additional melee and Scab elite enemies can spawn between waves, according to the game's random enemy spawning point system.

Specials will spawn at a normal rate when the Twins are up, and at 3 times the rate during the Tox Gas phases.

Rodin Karnak
Rodin has 3 general attack patterns:

• Shooting with his Plasma pistol
  
• A kick with large amount of push back
  
• Tossing his Tox Mines, which will arm themselves after a few seconds.

Rodin is the first Twin to first kill, due to his Tox Mines limiting the area players can fight in.
If in melee range, he can kick. His kicks and Plasma pistol shots can be easily dodged.

When a Tox Mine is triggered, they'll explode after a couple of seconds staggering the player and doing large amounts of toughness damage, or if the player is out of toughness, a decent amount of corruption damage.
They cannot kill the player, though will leave them at 1 HP.

If there aren't any Elites or other enemies to clean up, the wave killing Psyker should clear up the mines by triggering near the edge them then running out of their area.
Do not attempt to fully run through the mine's area, as most classes aren't fast enough.

Rodin has carapace armour on his head and upper left arm, with the rest of their body being unarmoured.
Rodin's shield takes in total 300% damage from melee, and 60% damage from ranged

Diagram for detonating Tox Mines safely:


Rinda Karnak - Melee Twin
Rinda has 3 general attack patterns:

• A dash, which will very briefly stagger the players she hits (will disrupt a Pskyer's Smite)
  
• A kick with large amount of push back
  
• Quick melee attacks
  
• A charged melee attack with a large area of effect attack

Rinda will continually pursue her target, attempting to stay in melee range, until switching to another.
She can be taunted by Ogryns, which is the main way of managing her.
Due to her using only melee attacks, with no other special moves, she's not as much of a threat as Rodin.

Be wary of her charged attacks, as they do hit behind her, and can hit a player from a longer range than expected.

Rinda's has carapace armour on her head and upper right arm, with the rest of their body being unarmoured.
Rinda's shield takes in total 200% damage from melee, and 100% damage from ranged

The fight consists of 7 phases, with 4 fight phases and 3 Tox Gas phases.

• Phase 1 is fighting the twins until one of them reaches 80% health.
  
• Phase 2 is the First Tox Gas phase, with the Tox Gas deployment lasting 30 seconds.
  
• Phase 3 is fighting the twins until one of them reaches 50% health.
  
• Phase 4 is the Second Tox Gas phase, with the Tox Gas deployment lasting 40 seconds.
  
• Phase 5 is fighting the twins until one of them reaches 20% health.
  
• Phase 6 is the Third and last Tox Gas phase, with the Tox Gas deployment lasting 50 seconds.
  
• Phase 7 is fighting the twins until they're both killed.

Tox Gas Phases
The arena consists of 2 halves, each with a Safe Zone.



Each Tox Gas Phase consists of the following:

• The twins despawn
  
• After a 5 second delay, the gas appears, but is non damaging
  
• For the First Tox Gas Phase, there's a 12 second delay before the Tox Gas becomes active, giving time to reach a Safe Zone. For the Second and Third Tox Gas phases, this is a 7 second delay instead
  
• The Tox Gas is deployed, starting the actual Tox Gas Phase
  
• After the random range of time (see Alternating Timings below), the Tox Gas becomes inactive, and the Safe Zone alternates to the other half
  
• After a 7 second delay, the Tox Gas becomes active again
  
• The above 2 steps repeat until the Tox Gas Phase has ended (timings mentioned in the list of Fight Phases above)

Standing in the Tox Gas while it's deployed will remove your toughness. If all toughness is removed, it will corrupt your health until you're at 1 HP.
This means toughness regenerating abilities and talents can help you survive or even make you near immune while standing in the Tox Gas.

Specials will spawn at 4 times the rate during Tox Gas phases.

Elite waves will still spawn during the Tox Gas Phases.
Additionally, sets of 25 Poxwalkers will spawn from the "West", "East", "North" and "Middle" of the arena during the Tox Gas phases.

Alternating Safe Zone Timings - First Tox Gas Phase

• Sedition, Uprising and Malice don't alternate sides on the First Tox Gas Phase.
  
• Heresy alternates sides between every 35 and 40 seconds on the First Tox Gas Phase.
  
• Damnation alternates between every 20 and 25 on the First Tox Gas Phase.
  
• Hard Mode Damnation alternates between every 14 and 18 seconds on the First Tox Gas Phase.

Alternating Safe Zone Timings - Second and Third Tox Gas Phases

• Sedition and Uprising alternates sides between every 40 and 45 seconds.
  
• Malice alternates sides between every 18 and 25 seconds.
  
• Heresy alternates sides between every 16 and 24 seconds.
  
• Damnation alternates between every 15 and 22.
  
• Hard Mode Damnation alternates between every 14 and 18 seconds.

• Doing the normal Damnation fight can be helpful in learning Rinda and Rodin's attack patterns
  
• The hard mode teleport bell can be unlocked at a lower difficulty, without having to go through the hard mode fight
  
  
• Prioritise taking down the elite waves before the bosses. The bosses are much easier to deal with once alone.
  
  
• Melee damage deals 100% extra damage to the Twin's shields
  
• Rodin's shield takes in total 300% damage from melee, and 60% damage from ranged
  
• Rinda's shield takes in total 200% damage from melee, and 100% damage from ranged
  
  
• Lower each of the Twin's shields first, before destroying them
  
• Make sure to kill Rodin first, to prevent him deploying his mines
  
• Once Rodin is eliminated, clear out his mines, so the team can much more easily kite Rinda
  
• You can sometimes abuse Rodin into continually doing kicks
  
• If you've learned Rinda's attack pattern, you can attack her during her wind ups
  
• Rinda's wind up attacks will damage you even if you're behind her
  
  
• Wound curios generally don't provide as much benefit, take a Health curio instead
  
• Having corruption resistance on your curios is recommended
  
• Chain weapon's special attack can deal large amounts of damage to the Twin's shields
  
  
• Always make sure to mark out elites and specials, so your Pysker and Veteran are aware of them
  
  Veteran
  
• Field Improvisation should apply to your whole squad, regardless of who deploys the Med Kit or Ammo Crate, however I've heard that sometimes this isn't the case
  
• If your Ogryn has used his Frag Bomb, drop down the Ammo Crate so he can restock his grenade
  
  Ogryn
  
• As an Ogryn, do not use your shield's special while staying still. Your health will be corrupted by Rodin's Tox bombs, leaving you at 1 HP
  
  Psyker
  
• Having a gun instead of a staff may be useful, due to Smite always keeping you at high peril
  
• Pskyers can dodge when using Smite. Dodge sliding (dodging then pressing crouch during the dodge] can also help reduce the chance of enemies staggering you out of Smite
  
• Use Venting Shriek when you're at 100% peril and still need to lock a wave down. This is much faster than quelling, and will stagger enemies
  
• Venting Shriek can also be useful to knock down and kill the Poxwalkers blocking your way when moving to the alternate Safe Zone during the Tox Gas Phases
  
• If you're confident in your peril management, then you can swap out Venting Shriek for Telekine Shield, with the Dome and Sanctuary modifiers
  
  Zealot
  
• Chorus of Spiritual Fortitude can be useful during the Tox Gas Phases, when moving to the alternate Safe Zone

Example builds:
Wave Killing - Psyker: https://darktide.gameslantern.com/builds/9ade3e35-5fa0-46d0-b34f-999f564b913a/twins-hard-mode-psyker-wave-killing

Wave Killing - Veteran: https://darktide.gameslantern.com/builds/9ade428f-04bb-4ce0-8a6f-55b6fcc09958/twins-hard-mode-veteran-wave-killing

Boss Management - Ogryn: https://darktide.gameslantern.com/builds/9ade442d-328c-42d0-8de0-f438bb424d7c/twins-hard-mode-ogryn-boss-management

Twins Event Script
https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/managers/mutator/mutators/mutator_toxic_gas_twins.lua

Elite Wave Compositions
https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/managers/mutator/mutators/mutator_toxic_gas_twins.lua#L776

https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/managers/mutator/mutators/mutator_toxic_gas_twins.lua#L440

https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/managers/mutator/mutators/mutator_toxic_gas_twins.lua#L1165

https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/managers/mutator/mutators/mutator_toxic_gas_twins.lua#L2394

renegade_assault = Scab Stalker
renegade_shocktrooper = Scab Shotgunner
renegade_melee = Scab Bruiser
renegade_executor = Scab Mauler
chaos_ogryn_executor = Scab Ogryn Crusher
renegade_berzerker = Scab Rager

Specials
https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/managers/mutator/mutators/mutator_toxic_gas_twins.lua#L845

Fight Phases
https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/managers/mutator/mutators/mutator_toxic_gas_twins.lua#L931

Tox Gas Phase Durations and Initial Alarm Duration
https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/managers/mutator/mutators/mutator_toxic_gas_twins.lua#L908

Tox Gas Alternating Timings and Delays
https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/managers/mutator/mutators/mutator_toxic_gas_twins.lua#L1053

Rodin Armour
https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/settings/breed/breeds/renegade/renegade_twin_captain_breed.lua#L409

Rodin Damage Multipliers
https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/settings/breed/breeds/renegade/renegade_twin_captain_breed.lua#L423

Rodin Armour
https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/settings/breed/breeds/renegade/renegade_twin_captain_two_breed.lua#L315

Rodin Damage Multipliers
https://github.com/Aussiemon/Darktide-Source-Code/blob/master/scripts/settings/breed/breeds/renegade/renegade_twin_captain_two_breed.lua#L417