Complex sentence: There he successfully rescues the Chalice from a group of Templars; the Chalice is Adha, the woman Altaïr knew and liked before the events of game.
Split into simpler sentences: There he successfully rescues the Chalice from a group of Templars. There it is revealed that the Chalice is a woman named Adha, the woman Altaïr knew and had feelings before the events of game.