From Lexicanum

Broodhives are a large network of Tyranid plants that tunnel underneath the surface. Underground the Broodhive resembles a network of giant, hollow roots. They allow tyranids to move undetected from one area to another.

Game Play

Broodhives may replace bunkers for tyranid forces.

Sources

• ¹:White Dwarf 254(us) "Hostile Terrain" by Pete Haines

See also

• Species of Tyranid