The Legend of Heroes: Trails in the Sky SC

In the aftermath of the previous game's ending, Joshua has disappeared and Estelle is eager to bring him back home. After completing some training by the Bracer Guild to prepare for her new adventure, Estelle is ready to set out. While Cassius resumes military duties in light of recent events, Estelle reunites with all of her other allies from the previous game, as well as a new one, Septian Church knight Kevin Graham, to resolve a series of incidents all over Liberl caused by experiments run by the Enforcers of Ouroboros - an organization which Joshua himself was a former Enforcer of. The Enforcers prove to be devastatingly powerful and their experiments disrupt and endanger Liberlian lives, but thanks to the group's efforts, casualties are prevented. The Enforcers, some of whom have connections to various members of Estelle's group, are being led by the organization's Third Anguis, Georg Weissmann, who used the alias of "Professor Alba" in the previous game. Weissmann is seeking to use their experiments to help unearth an ancient treasure sleeping in the country: the Aureole, the Sept-Terrion of Space (the Sept-Terrions are a group of seven treasures in the series with enormous power, given to the series' world by its goddess). During this time, Joshua, with the help of the sky bandits, runs a vendetta against his former organization to thwart their plans, doing so without Estelle to avoid endangering her.

Estelle is eventually kidnapped by the organization and taken prisoner on their flagship, the Glorious. During this time, Estelle is told the truth of Joshua's past by lead Enforcer Loewe (who used the alias of "Lorence Belgar" in the previous game). Loewe and Joshua lived a peaceful childhood in the Erebonian town of Hamel. 10 years ago, Hamel was massacred by its own government, which framed Liberl for the attack in an ultimately unsuccessful plot to annex it by force (this led to the Hundred Days war during which Estelle's mother died). Loewe and Joshua were the sole survivors of the massacre, and the then-six-year-old Joshua was traumatized due to the death of his sister (also Loewe's lover), and being forced to take the life of a soldier. Afterwards, Weissmann mended Joshua's catatonic state in exchange for him and Loewe becoming Enforcers in his organization. Joshua later left the organization once he was adopted by Cassius, but Loewe remained, and is the most powerful Enforcer active in Liberl.

Estelle is almost able to escape the ship, but ends up cornered by the society's forces. Joshua arrives to save Estelle and escape the ship with her, and the two reconcile and reunite. They then team up with all of their allies in a final effort to end Ouroboros's schemes. Ultimately, they are unable to prevent Ouroboros from reactivating the Aureole, causing an enormous floating city - the Liber Ark, the historical predecessor to Liberl - to appear from another dimension. The appearance of the city causes a nation-wide stoppage of orbal devices (leaving Liberl without power) by drawing all the power to the city. As this Orbal Shutdown Phenomenon extends to the southern reaches of Liberl's neighbor, Erebonia, Erebonian forces nearly invade Liberl. However, thanks to the intervention of Olivier Lenheim - whose true identity is Olivert Reise Arnor, the Crown Prince of Erebonia - the Liberl group is given time to resolve the crisis before the Erebonians intervene. Despite him keeping his identity a secret all this time, Olivert remains an ally to and part of Estelle's group.

The group lands on the floating city and battles all of the Enforcers. Joshua finally manages to defeat Loewe and break his loyalty to the organization. However, Weissmann subdues Loewe and takes control of Joshua by using a Stigma he had long ago implanted in the traumatized boy. The Stigma is a powerful technique from the Septian Church that can raise the physical limits of its subject. Weissmann, a former bishop, was excommunicated from the church years ago after he was proven to be artificially creating Stigmas for nefarious purposes, something strongly condemned by the church. Weissmann orders the mind-controlled Joshua to kill Estelle, knowing this would break his spirit; however, earlier, Joshua predicted that this is specifically what Weissmann would try to force him to do, and due to hypnotic suggestion by Kevin - requested by Joshua on Cassius' suggestion - the order causes Joshua's Stigma to break, freeing him from Weissmann's control.

Realizing his plan is falling apart, a desperate and now unhinged Weissmann fuses with the Aureole and overpowers the party. Loewe intervenes, and during this time, it is revealed that Weissmann was responsible for inciting the tragedy of Hamel. Loewe then gives his life to save the party, to Joshua's sadness. As the group mourns Loewe after defeating Weissmann, the city begins to fall out of the sky since only residual power from the Aureole remains, forcing them to evacuate. Shortly afterwards, Weissmann, who managed to survive Loewe's counterattack, is murdered by Kevin, who in reality was dispatched to Liberl to assassinate Weissmann in retaliation for his betrayal of the church and theft of its techniques. In the aftermath of this, Campanella, an Enforcer who was merely acting as an observer for the plan, retrieves the Aureole from Weissmann's remains and disappears. The rest of the party is able to escape the collapsing city, but Estelle and Joshua appear trapped.

They are able to escape thanks to the sudden appearance of Cassius. In the game's epilogue, Joshua and Estelle share a moment near the grave of Joshua's sister, where Loewe himself has now been buried, and the spirit of Joshua's sister looks on in happiness.