Are these sentences properly worded?

FYI- Szass Tam is the undead wizard, the Council is the mage-lords, and the southern army serves them. Neither the mage-lords nor any of their followers could defeat the dream vestige, and as the Council’s legions fell back before the mighty undead entity and their formations collapsed, Malark entered the fight and made his way to Dmitra, whom he proceeded to kill. Although Szass Tam soon sent the dream vestige to its astral domain in order to keep the creature from escaping his control, the remnants of the southern army could not withstand the undead wizard’s forces and had to retreat south.