The Parhelion was the great hall where the Boros angels of Ravnica resided. It was first constructed as a skyship in an attempt to find out about Ravnica's planeswalker visitors who had stopped coming, but when the angels flew it to the edge of Ravnica's existence they encountered only emptiness. It was later repurposed as the Boros headquarters. It was located high above the city of Ravnica, amongst the clouds. In times of war, the Parhelion would descend and dock with Sunhome.
The angel Feather was restricted from the Parhelion for some unknown reason, and as punishment her wings were bound and she was forced to serve the Wojek, amongst normal mortals. An unknown time later, Szadek, who was enslaved by Augustin IV at the time, managed to gain access to the Parhelion and managed to kill its residents. He then planned to use it to destroy Prahv and the Guilds. Although his plan was stopped by Agrus Kos, the Parhelion was destroyed.
The Parhelion was rebuilt as the Parhelion II, also known as the Response Garrison and is used by the Boros as a flying fortress. It is home to the Boros angels, with skynights making up a significant portion of its soldiers. It houses two floating warships.