The die is cast
Condition: clear Rainy Days Never Stay
Location: Talk to Yagiya at Nakano Campsite to teleport to Shinagawa Catacomb of the Templar Knights (Alternate).
Experience: None
Guide:
Talk to Gryphon NPC in Shinagawa Catacomb of the Templar Knights (Alternate).
South Route leads to Diana for a fight, then again for another fight.
Diana first fight
Barong will respawn infinitely but don't worry, kill one and you will get a repel buff. Go to Diana and let her hit you once to reflect her own attack then kill another Barong, repeat until she's dead. The second fight will be normal.
North Route leads to Abraxas for a fight, then again for another fight.
Abraxas first fight
Kill each group of demons once until you get Efreets, then you can focus on killing Abraxas. The second fight will be normal.
Talk to Gryphon and go to Black Maria for a fight.
Black Maria first fight
Defeat Flamies ⇒ Aquans ⇒ Earthies (leave Aeros alive or they will all respawn again) in this order or Black Maria will be invincible. Defeat her to finish quest.
You can teleport to this area and repeat the fights anytime.
If you defeat Black Maria before any Wil o'Wisp suicide or be killed, you get Black Maria plugin.