Mobs Ethereal Bosses
DuckGo

Add Bosses to "Ethereal NG" biomes!

Wilhelmines People
Liil

Adds the possibility to build living Villages. Trade items for random stuff from your villagers, recruit mounts and warriors.

Forgotten Monsters
DuckGo

Monsters and Bosses...

Wisps
ElCeejo

Adds non-entity mobs called Wisps

Native Villages
Liil

Adds villages of native people to the world.

Power Rangers Modpack
LC Creations

Adds power rangers and an API to create your own.

Grave
ElCeejo

Adds an eerie biome with multiple mobs.

Ocular Networks
PolySaken

Draw power from the world, and use it to power machines and tools.

Banshee
ElCeejo

Adds Banshees, a ghostly mob that haunts pine forests