How Ynnari protect themselves from Slaanesh?

Question

Every Eldar is at risk of losing his/her soul to She-Who-Thirsts. Fortunately, there are ways to protect themselves from that:

Craftworld Eldars wear spirit stones and follow strict mental Paths, that lock them for years into one state of mind, therefore reducing the chance of falling prey to the indulgences of Slaanesh. When such Eldar dies, his soul is transferred to the stone and then to the crystal Infinite Circuit.

Exodites are protected by the World Spirit - a spiritual being protecting the Maiden World where they reside. If they would ever leave their home planet, they would be completely unprotected.

Harlequins are almost certainly immune and there are two versions regarding this immunity: one said that they are simply protected by Cegorach, the Laughing God. Another one says, that each candidate has to undergo a possession by the demon and then they need to exorcise the said demon by using their own will, which makes them immune from further demonic influences.

Dark Eldars are the most influenced by She-Who-Thirsts, and their souls are constantly drained by Her. But instead of protecting themselves from it, they keep replenishing themselves by causing pain and torture to others.

The newest group is called Ynnari - those are the followers of the nascent god of death Ynnead. Eldars from all groups flock to them looking in hope for the future - but how do they protect themselves from Slaanesh? Are they following the old ways (so Dark Eldars keep they happy tortures while Craftworlders live like ascetic monks) or is Ynnaed strong enough to protect them?

Answer 1

Concerning the Harlequins: the ones with the possible possession are the Solitaires.

The most chilling of all the Aeldari Harlequin are those individuals known as a Solitaire, called in the Aeldari Lexicon the arebennian. The Solitaires, as their name implies, are solitary individuals who roam the universe alone for most of his life, occasionally joining a masque for a single performance or battle as the fancy takes him. He speaks and is spoken to only in ritual form, and when he is not performing he rarely communicates with the other Aeldari. The most startling truth of the Solitaires is that, unlike other Harlequins, who are protected by their faith in Cegorach, their souls are doomed to be devoured by Slaanesh, although the Laughing God attempts to intercede on the Solitaire's behalf after their death and force the Prince of Chaos to compete for his or her soul. Whenever Solitaires are with a Harlequin troupe, they prefer to distance themselves from the others, and one is considered cursed if one exchanges words with a Solitaire. A Solitaire never shows any sign of emotion, either with other Harlequins or on the battlefield. Psykers of every race, even other Aeldari, are known to be very depressed in the presence of a Solitaire. The mental landscape of the Solitaire is obviously disturbing to them. Psychic attacks on Solitaires will almost always fall short, and weapons which attack the enemy's mind, such as the Neuro Disruptor, will simply have no effect.

This is similar to the Exorcists Astartes Chapter:

The Chapter was created through secret Inquisition experiments in which test subjects were deliberately allowed to be possessed by daemons for a time before the daemons were banished by Ordo Malleus Inquisitors. There were casualties, but the majority of test subjects survived and emerged unusually skilled in the ways of combating daemonkind as the Inquisition had hoped.

This has also caused the subjects to have no psychic signature that psykers can detect. The original test subjects, some two companies strong (200 Space Marines) were released onto a daemon-infested planet on the northern fringes of the Eye of Terror where they displayed extremely impressive results, achieving a kill ratio of 97:1.

Concerning Ynnead:

He will be so powerful that it has been foreseen that a new dimension will be created, alongside the Immaterium and the material universe, that will be a part of Ynnead. It has also been foreseen by the Aeldari that all of their souls will be forcibly pulled to Ynnead when they die, instead of being drawn into the Warp to be consumed by Slaanesh.

So, it will be the same as with Cegorach