New mobs + details
Delver
The Sifting
A Creaking variant found in the sift
Primal Sifter
+16 new mobs
Sift biomes
???
More details needed
Existing siftlings
High Council + members
Rift staff + rifts
Pages needed
Primal Sifter
Baby Sifter
Rifts (they can appear across the overworld rarely, or can be opened with a rift staff)