Aspect of the Crawling Matriarch
Aspect of the Crawling Matriarch has 1,700 health.
It resists pierce; spirit does nothing to it at all. Blunt and slash land at full damage, so that is what to bring.
Nothing but a player can damage it, so tames, Dvergr and summoned companions do nothing for this part of the fight.
Its hardest hit is bite at 100 pierce and 100 poison, out of 5 attacks.
Some of what it throws is elemental, so poison resistance is worth having.
Of everything craftable, 
Lightning Strike, 
Frostfire Sledge and 
Frostfire Greatsword put the most damage through what it resists.
Aspect of the Crawling Matriarch is a phantom copy of 
The Queen that 
Kall Fimbulbringer summons during his second phase. It has 1,700 health, resists pierce and ignores spirit damage, but its head is a weak spot that takes extra damage from blunt, slash, pierce, fire, frost and lightning alike, so aim high. It crawls at 2 and charges at 8, the widest gap between walking and running speed of any aspect, and only a player can damage it.
This is a positioning fight, not a damage one. Nothing she does hits especially hard, but every connection puts you across the room and usually into another aspect. She is resistant to pierce and nothing else, so blunt and slash both work. Fight her with your back to open floor.
With devcommands enabled, this spawns Aspect of the Crawling Matriarch in front of you. The third number is the level: 3 spawns a 2-star.
Creature ID: Aspect_SeekerQueen · all console commands and IDs