It's been five years since the Sisters of Parvos first swaggered into the Origin System, and I'm still hunting them. Introduced back in 2021 with the Call of the Tempestarii update, these Corpus super-soldiers rapidly became one of the most addictive endgame loops Warframe has ever offered. They're arrogant, they're deadly, and they'll steal your hard-earned resources right from under your nose – but the promise of a new Tenet weapon or a converted ally keeps me coming back. Over the years, the mechanics haven't changed dramatically, but the thrill of deciphering Requiem sequences and that final confrontation aboard a railjack never gets old. Here's everything I've learned about spawning, angering, and permanently putting down your own Sister of Parvos.

Earning the Right to Hunt

Before you can even think about generating a Sister, you need to clear two pivotal quests: The War Within and Call of the Tempestarii. The former unlocks your Operator and the broader nemesis system, while the latter introduces Vala Glarios and the lore behind Parvos Granum's chosen warriors. Once those are in your Codex as completed, you're ready to spawn a Candidate.

Candidates appear on any mission that uses the Corpus Ship tileset, but only after you've entered the Granum Void with a Zenith Granum Crown and reached at least the Rank 1 Nightmare difficulty reward threshold. If you're new to this, that means you need to find a golden hand statue on the map, interact with it while carrying a Zenith Crown, and then kill enough Errant Specters inside the Void to hit the first reward tier before the timer expires. Once you return from the Void, a Candidate has a high chance of spawning somewhere in the level. Down them, walk up, and perform a Parazon Mercy Kill – that act creates your very own Sister. It's important to note that before you land that final blow, the downed Candidate will flash the icon and name of the Tenet weapon she'll carry. If you don't like what you see, you can simply ignore the Candidate and extract to try again later. I've burned many a mission doing this to get the exact Arca Plasmor or Cycron I wanted.

Managing Her Territory and Rage

Once created, your Sister wastes no time. She grabs a few nodes on the Star Chart and begins taxing your mission rewards from those spots. The only way to reclaim those stolen goodies is to defeat her for good, so consider it a forced savings account. Besides the theft, all nodes under her control become “Sister Controlled Territory” missions, swarming with mechanical Hounds she deploys. These Hounds are more than just cannon fodder – each one you kill contributes to her anger meter, which goes from Indifferent → Annoyed → Fuming → Furious → Enraged. The angrier she gets, the more likely she is to show up mid-mission to wreck your day.

When she does appear, she brings a formidable shield and three health bars. Burst through her shield and whittle down a health bar to 5%, and she'll drop to one knee, giving you a brief window for a Mercy attempt. If you don't have the right Requiem mods equipped, you'll fail the finisher; she'll stagger, curse you, gain a level, and vanish. She also levels up and spreads to a new planet if you clear all her Controlled Territory nodes before confronting her. Each rank-up shifts her influence to a tougher planet, and the enemy levels scale accordingly:

A Rank 5 Sister can be a real challenge if you're not geared for level 100+ content, so I always try to figure out my Requiem sequence before she spirals out of control. Blue clouds on the Star Chart make her influence easy to spot.

Cracking the Requiem Code

Killing Hounds isn't just about anger management – it's your primary way to earn Requiem Murmurs. Each Hound execution fills a progress bar, and once it's full, your Sister's status page reveals one of the three Requiem mods needed to kill her permanently. The catch? Murmurs won't tell you the correct order. That's on you to brute-force. I equip my Parazon with the three revealed mods in a random arrangement, then hunt the Sister in her territory. When I get her down to a Mercy window, the game checks the first mod; if it's right, the finisher succeeds and destroys one health bar, then moves to the next mod. If any mod is wrong, the Sister recoils, ranks up, and leaves. It's a trial-and-error loop, but you can speed things up by equipping the Oull requiem mod (a universal wildcard) if you've got one, or by using intuition to rearrange based on which mods are failing at which step.

A crucial combat tip: Sisters always bring their Hound to the fight. If the Hound is still alive when you deplete the first health bar, it will self-destruct in a damaging radial blast and deny you Murmur progress. So I always kill the Hound first. Also, beware of Corpus Shield Ospreys – they can instantly restore the Sister's entire shield if they link to her. Some veterans swear by Radiation procs to prevent the link, but I find it safer to simply nuke the Ospreys the moment they spawn.

The Final Showdown and Your Big Decision

Once you've cracked the full Requiem sequence, the Sister doesn't just die on the spot. Instead, she flees to her capital ship in Neptune Proxima, creating a dedicated node called Sister Confrontation. You'll need your Railjack for this. Blast through the escorting Crew Ships, board the capital ship, and fight your way to her sanctum. Inside, she's waiting with her Hound and two random Warframe specters – and she's straight-up invulnerable until both specters are destroyed. Once they're down, she fights with a single massive health bar. Deplete it, and you'll get one last Parazon prompt.

Here comes the 20-second decision that defines your reward:

• Vanquish gives you her Tenet weapon (bypassing Mastery Rank requirements!) and her Hound as a companion. Both appear ready to claim in your Foundry, and all teammates get a random Hound component blueprint.

• Convert turns her into a permanent ally. She'll randomly appear to aid you when you bleed out, and you can assign her as a defender on your Railjack crew. Either way, you get back every credit and resource she stole from you.

Don't overthink it during the countdown – if you let the timer run out, the game auto-selects Vanquish. I typically vanquish unless I roll a Sister with a really rare ephemera or a quirk I want to show off in Railjack missions.

Bonus Tips from the Trenches

• Ephemera farming: When a Sister is created, she has a 20% chance to come with a special cosmetic ephemera, like the glowing Zarina ornament in the image below. You get this regardless of whether you vanquish or convert her, so always check her appearance before you start the hunt. Some ephemeras remain incredibly rare even in 2026, and fashion frame is the true endgame.

• Quirks: Sisters can spawn with behavioral quirks. For example, Paranoia makes her attack nearby Corpus allies, which can distract her during fights. Fear of Being Alone triggers amusingly desperate dialogue when she's isolated. These quirks add flavor and sometimes a slight tactical advantage.

• Steel Path considerations: If you really want a challenge (and a higher resource drop chance), run the entire Sister hunt on Steel Path. The higher enemy density makes Murmur farming faster, but a level 5 Steel Path Sister can one-shot unprepared frames.

• One at a time: You can't have both a Kuva Lich and a Sister active simultaneously. If you've got a Lich hanging around, you'll need to vanquish or convert it before a new Candidate will spawn. Plan your nemesis queue accordingly.

The Sisters of Parvos system remains one of Warframe's most engaging player-driven loops in 2026. The blend of tactical preparation, persistent theft, and final heroic confrontation – paired with an ever-expanding arsenal of Tenet weaponry – ensures I never stay away from the Corpus Ship tileset for long. Whether you're a Tenno looking for your first Spirex or a veteran chasing that elusive 60% magnetic bonus, there's always a Sister out there waiting to make your life difficult. And honestly, I wouldn't have it any other way.