Propagator Core XR-53 is the Boss of the Relentless Replication Operation in Star Wars The Old Republic. This guide will easily teach you everything you need to know to defeat XR-53 in Story Mode and Veteran Mode.
Contents – Click to Jump
How to Start
The entrance to the Propagator Core XR-53 boss lair can be found on Ilum inside your Faction’s Base next to the entrance to the False Emperor Flashpoint. There is also a Quest Terminal outside of the room that allows you to pick up the [Weekly] Quest: Relentless Replication for completing the raid.
To complete the Relentless Replication quest, you must defeat the Propagator Core XR-53 in any difficulty. Completing the Relentless Replication mission rewards you with 5 Ancient Stepped Altar stronghold decorations.
Story mode: XR-53 has 30 million Hitpoints and can easily be defeated if DPS can parse 12-15k or higher.
Suggested Roles: 1 Tank, 1 Fake Tank (any DPS capable of taunting), 4 DPS, 1 Solo Healer.
Veteran / Hard mode: XR-53 has 50.559 million Hitpoints and can easily be defeated if all DPS can parse 22-25k or higher.
Suggested Roles: 1 Tank, 1 DWT, 4 DPS, 1 Solo Healer.
If you have no Tanks or are using only 2 DwTs, consider taking 2 Healers. Both Storymode and Hardmode can be completed by a Solo Healer in 340 gear.
Simple Guide
Propagator Core XR-53 has no phases, but instead repeats the same set of mechanics until it is killed, or you reach the fourth Prime Directive (Enrage).
Standard Comp: 2 Tanks, 4 DPS, 2 Healers.
Always have Tank facing the boss away from the group (towards the wall), have all DPS and Healers stack in melee range behind the boss. All players should avoid Green Acid and all Red Circles/Square attacks.
Kill ALL Adds ASAP in this Priority:
1. Prime Directive Droid – Always kill first!!!
2. Prey Seeker (Stun Droid) – Kill ASAP, ignore Imperfect Construct if you have to.
3. Imperfect Construct – Devote 2-3 DPS players to killing Imperfect Construct if no Stun Droids are alive. Not a problem if a few live.
Orange Fire Debuff – Digestive Enzyme
The Digestive Enzyme (Orange Fire) Debuff adds a stack everytime you take AOE damage, stand in Green Acid or any Red Circle.
The more stacks you have, the more damage you take from everything.
Storymode: the stacks will dissappear after 30 seconds.
Vet/Hard mode: You can only cleanse 10 stacks at a time while standing inside XR-53’s Hungering Bite attack (large Orange Square). Try to never have more then 10-15 stacks in Vet/Hard mode.
Softened Up Debuff – Tank Swap Mechanic
The Softened Up debuff (White/Red Laser) is given to whoever has aggro of the Boss when XR-53 casts Lethal Strike. You should always Tank Swap after each stack of the Softened Up debuff.
Getting two or more stacks will kill any Tank.
Extraneous Explosion: Tank must face the large red square away from the group, all players inside the large red square will cause Green Acid to spawn on the ground and gain Orange Fire debuff stacks.
Prime Directive (Mandatory): XR-53 will surround himself with a Large Orange Circle for 10 seconds. There are 3 Prime Directive Casts in the fight, if he casts a Fourth Prime Directive, he will Enrage and your group will wipe (occurs after 10 minutes).
Story Mode: Any group of players can stand inside the Orange Circle, boss will spawn a Construct that needs to be killed ASAP before anything else.
Vet/Hard mode: All players of one Role type must be alive inside the Orange Circle before time runs out. Once one role type has done the Prime Directive, they cannot do it again:
Defender Construct: Spawns if Tanks stand inside the circle, makes XR-53 immune to all damage until it is defeated.
Rampaging Construct: Spawns if DPS stand inside the circle, deals constant raidwide AOE damage and must be killed quickly.
Supplicant Construct: Spawns if Heals stand inside the circle, the Supplicant will attempt to Heal the boss for a lot of HP. Players must alternate using their Interrupt abilities on the Supplicant until it is defeated.
Best Order: DPS in first Prime Directive, Healers in second Prime Directive, Tanks in third Prime Directive.
Mistaken Construct: Spawns in all difficulties during the 4th Prime Directive or if you fail or repeat a role. The Mistaken Construct will spawn and kill everyone in a few seconds.
Mechanics
As the Propagator Core XR-53 has 30 million HP in Story mode and 50.55 million HP in Vet/Hard mode, it is best to position XR-53 around the middle of the room.
DPS, Healers and the Off-Tank/DWT should stand in a big group behind the boss at all times.
You should only stand infront of the boss when XR-53 is casting the Hungering Bite (to cleanse stacks) or Prime Directive if it is your turn (Vet/Hm only).
The priority order of add droids are ALWAYS as follows:
1. Prime Directive Droid – must always be killed first as they can cause your group to wipe.
2. Prey Seeker Stun Droid – must always be killed above Imperfect Constructs as they can stun players taking damage.
3. Imperfect Construct Acid Droid – are important to kill as often as possible, but not a big deal if you do not kill all of them.
Stun Droid – Priority DPS Mechanic
Every 40 seconds a Prey Seeker stun Droid will spawn and stun a random player for 20 seconds.
Prey Seeker Droids should be killed ASAP even if it means ignoring an Imperfect Construct droid.
If the 20 second Stun Channel finishes before the Stun Droid is defeated, it will deal AOE damage to all nearby players.
Storymode: 155k HP, can be killed quickly by 1-2 DPS.
Vet/Hardmode: 388k HP, can be killed quickly by 3 DPS.
Red Circles – DPS Mechanic
Roughly every 20 seconds XR-53 will shoot small red circles at every player.
Run outside of the red circle otherwise you will take damage and gain a single Orange Fire Debuff stack.
Imperfect Construct
Every 20 seconds an Imperfect Construct Droid will spawn and leap towards a random player.
When the Imperfect Construct has jumped on a player, it will begin casting an ability called ‘Imperfect Explosion‘ which takes 15 seconds. If you do not kill the Imperfect Construct before time runs out the droid will explode and put Green Acid on the floor for the rest of the fight.
Standing inside of the acid deals damage over time and increases your Orange Fire Debuff. It is not a big deal if you do not kill every Imperfect Construct, but you should try to kill as many as possible.
Storymode: 155k HP, can be killed before explosion by 1-2 DPS.
Vet/Hardmode: 388k HP, can be killed before explosion by 3 DPS.
Hungering Bite – Cleanse Stacks
Orange Fire Debuff – Digestive Enzyme
The Digestive Enzyme (Orange Fire) Debuff adds a stack everytime you take AOE Damage, stand in Green Acid or any Red Circle.
The more stacks you have, the more damage you take from everything.
Story mode: The Digestive Enzyme debuff will automatically be removed if you do not get another stack after 30 seconds. It can also be cleansed by Hungering Bite.
Veteran / Hardmode: The Digestive Enzyme debuff does not expire, it will stay permanently until you cleanse it with Hungering Bite. You should never have more then 10-15 stacks of Digestive Enzyme at a time!
To remove the Digestive Enzyme, you need to stand inside XR-53’s Large Orange Square ability called Hungering Bite. You have 3 seconds to stand inside the Large Orange Square to cleanse your stacks when XR-53 says “Mmmm just a taste”.
In Story mode it will remove ALL stacks.
In Veteran / Hardmode it only removes 10 stacks!
Extraneous Explosion
Every 30 seconds XR-53 will cast Extranous Explosion (green icon). Any player inside the large Red square will take damage and also spawn Green Acid under their feet.
Only one Tank should be standing inside the large Red square, and face it away from the group.
Lethal Strike – Tank Swap
Every 30 seconds, XR-53 will cast Lethal Strike which applies the Softened Up debuff to the player with Aggro of the boss.
You may be able to use abilities such as Shroud, Saber Reflect or Sonic Rebounders to cheese a stack.
Softened Up Debuff – Tank Swap Mechanic
The Softened Up debuff (White/Red Laser) is given to whoever has aggro of the Boss when XR-53 casts Lethal Strike. You should always Tank Swap after each stack of the Softened Up debuff.
Getting two or more stacks will kill any Tank.
Lethal Strike / Softened Up debuff is a Tank Swap mechanic. A DPS or Healer player should never have aggro of the boss, therefore should never recieve the debuff.
The moment the main Tank has a stack of Lethal Strike, the Off-tank/DWT needs to take over until the main Tank’s Debuff expires and they can take over again.
If your Tank and Offtank/DWT can swap effectively, this mechanic becomes a non-issue for the rest of the raid.
Prime Directive – Mandatory Mechanic
Prime Directive is a mandatory Mechanic that is easy in Story mode and complex in Veteran / Hard Mode.
You will know when the Prime Directive mechanic has started as XR-53 will surround himself in a large Orange Circle.
Propagator Core XR-53 starts the Prime Directive mechanic on a timer, you have ten seconds to stand inside the Orange Circle.
There are 3 normal Prime Directives, the 4th Prime Directive is an automatic Enrage and will cause the group to die:
Prime Directive 1: 2 mins 30 seconds
Prime Directive 2: 5 mins 15 seconds
Prime Directive 3: 7 mins 30 seconds
Enrage Prime Directive 4: 10 mins 15 seconds
In Story Mode: at least one player needs to stand inside of the Orange Circle before the timer runs out. XR-53 will then spawn a Powerful Construct droid which must be killed by all DPS before you start fighting the Boss agian.
In Hard Mode: All players of one Role Type (Tank, DPS, Heal) must be alive and stand inside the Prime Directive, Once players from a specific Role have done the Prime Directive, they cannot do it again.
Best Order: DPS in first Prime Directive, Healers in second Prime Directive, Tanks in third Prime Directive.
Defender Construct 4million HP: Spawns if Tanks stand inside the circle, makes XR-53 immune to all damage until it is defeated.
Rampaging Construct 3.1million HP: Spawns if DPS stand inside the circle, deals constant raidwide AOE damage and must be killed quickly.
Supplicant Construct 3.1million HP: Spawns if Heals stand inside the circle, the Supplicant will attempt to Heal the boss for a lot of HP. Players must alternate using their Interrupt abilities on the Supplicant until it is defeated.
Suggestion: DPS first Prime Directive as it is the slowest and easiest, Heal second Prime Directive and Tank third Prime Directive.
Mistaken Construct – Fail: The Mistaken Construct spawns if you either fail to have all players of one Role inside of a circle OR you have not defeated the boss before the 4th Prime Directive. The Mistaken Construct will kill your group in seconds.
Rewards
Story mode:
All players will recieve 1-5 Corrupted Bioprocessors.
There is a small chance one random player will recieve one of the following Augment 83 Schematic: Absorb Augment 83
Schematic: Accuracy Augment 83
Schematic: Alacrity Augment 83
Schematic: Critical Augment 83
Schematic: Redoubt Augment 83
Schematic: Shield Augment 83
Schematic: Versatile Augment 83
Veteran / Hard mode:
All players except one will recieve between 12-18 Corrupted Bioprocessors. One random player may recieve a Bag of 20 Corrupted Bioprocessors as well.
There is a small chance one random player will recieve one of the following Augment 86 Schematics instead of a Processor Bag:
Schematic: Absorb Augment 86
Schematic: Accuracy Augment 86
Schematic: Alacrity Augment 86
Schematic: Critical Augment 86
Schematic: Redoubt Augment 86
Schematic: Shield Augment 86
Schematic: Versatile Augment 86
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