40k lore - The Sisters of Silence are back, and they are many!

Howdy Guys and Girls - little fluff blob about the Sisters of Silence, via Black Library:

"Also known as Null-Maidens, the Sisters of Silence are witch-hunters supreme. Each is psychically untouchable, immune to mental assault and with no presence at all in the mirror dimension of the Warp. No war cry comes from the throats of the Golden Throne’s witch-seekers, no shouted commands direct the ebb and flow of their attack. Only the crack-boom of the holy bolter and the whooshing roar of flamers accompany their eternal hunt for those who would bring Chaos to the Imperium."

"In the years since the Horus Heresy, their numbers have grown, gradually but steadily, into the tens of thousands. Now the Sisterhood is a vast army of psychic nulls, standing ready to extinguish the dark flames of Chaos that threaten to consume the Imperium."

"The knowledge needed to create and maintain their more exotic transports from the age of the Horus Heresy having been long since forgotten or locked away."