Are these sentences correctly structured and worded?

FYI- The zulkirs are the Council, Tsagoth is the blood fiend, and Tammith is the vampire. Since his forces were losing the battle, Szass Tam used the last of the power that Bane gave him to once again summon the dream vestige. As the fog-like entity started to eradicate the Council’s followers, the zulkirs’ Red Wizards and priests attempted to stop it, but they were unsuccessful. While Aoth and Brightwing flew over the dream vestige in an attempt to find a weakness by learning about the creature’s nature, Tammith was assailed by Tsagoth. Bareris, Winddancer, and Mirror soon came to Tammith’s aid and joined the fight, but when the four nearly defeated Tsagoth, the blood fiend tackled the vampire into the sea, where the water completely immobilized her and began to slowly dissolve her body into nothingness.