Having already destroyed both the Obelisk and Resurrection Cauldron, the group defeats the army of golems and proceeds to the top of the tower. There they find a beautiful garden, but Riannon senses a disturbing presence.
With the Gravitas enchantment hindering their defenses, Arawn and Ogam split off to find the source. As the others hold their ground against the enemy, the power of the Gravitas increases and threatens to crush the Gaels' force.
Taliesin's sacrifice has stopped the enemy in their tracks, but Arawn knows swift actions are needed to defeat them. Arawn leads the Gaels to Palladium, while the others go in search of the sword Dyrnwyn.
Taliesin gets a glimpse of Arawn's past which reveals the actions Taliesin must take. The black knights are lured into the mountains and Arawn's forces keep them at bay while the Giants create an avalanche.
With her husband injured and her brother gone, Riannon must take command of the tribe and repel the invasion of Avalon by Gaius' forces. A group of Gaels, including Morgan and Octavia, are encamped outside the castle.
As the Imperial forces gather around them, Arthur makes the impulsive decision to lead a preemptive strike. The group passes through the forest and enters an area under the enchantment of the Gravitas.
The tribe is running low on supplies and funds, so Arawn takes Arthur and a group to his tomb to collect some of the treasure there. Upon arrival, the group is attacked, first by Talos, then by an ogre.
The Rubrum learn the location of Avalon Castle, causing the Gaels to suspect that Octavia is a spy. The Gaels fight again with the Rubrum, and Octavia gets the chance to settle her score with Lidia once and for all.
The tribe heads for the elfin city of Avalon, where Limwris and Ermin are met. Entry into the castle seals the tribe's decision to fight in the coming war. The elves learn that Arthur and Riannon are the children of King Pwyll.
The villagers prepare to leave for Albion, but their ship has been captured by the Imperial Army. To make amends for her failure to defend their ship, Morgan tries to kill Arawn, who easily subdues her attack.