Scarlet Keep

The Scarlet Keep is a massive Hive fortress recently established on the Moon. Its construction was overseen by Hashladûn, Daughter of Crota, who designed it to harness the energies of a Pyramid buried in the chasm beneath.

Overview
The Scarlet Keep's central tower, the Tower of Woe, acts as an amplifier for Hive magic.

The Keep appears to be gradually overtaking other nearby Hive structures, as patches of red, spined architecture can be seen within the Hellmouth, The World's Grave and Temple of Crota.