Overlord Season 4 Explained: Story, Major Battles, and Ending

Overlord Season 4 continues Ainz Ooal Gown’s rise as the ruler of the Sorcerer Kingdom, shifting the focus from isolated battles to political strategy and large-scale warfare. Following the events of Season 3, Ainz seeks to strengthen his nation’s influence through diplomacy, trade, and military power. However, his attempts to establish peaceful relations gradually spiral into conflicts that reshape the balance of power across the New World.

Rather than concentrating solely on Nazarick, the season also explores neighboring kingdoms and empires, showing how rulers, nobles, and adventurers react to the growing influence of the Sorcerer Kingdom. Alongside political intrigue, viewers are treated to several major battles that demonstrate the overwhelming strength of Ainz and the Floor Guardians. Here’s a complete explanation of what happens in Overlord Season 4 and the key battles that define the story.

Season 4 Story Explained

Season 4 begins with Ainz attempting to transform the Sorcerer Kingdom into a stable nation recognized by the rest of the world. Hoping to improve diplomatic relations, he encourages trade with neighboring countries while allowing merchants and visitors to interact with his undead-led kingdom. Despite these efforts, fear and misunderstanding continue to shape how other nations view Nazarick and its ruler.

One of the season’s earliest storylines follows the Dwarf Kingdom Arc, where Ainz travels to the Azerlisia Mountains in search of skilled rune craftsmen. During this journey, he forms an alliance with the dwarves while helping them reclaim their homeland from the invading Quagoa. The campaign introduces new races, expands the world-building, and further strengthens the Sorcerer Kingdom’s influence beyond its borders.

Another major storyline focuses on the Holy Kingdom, although much of that narrative is adapted separately in Overlord: The Sacred Kingdom. Within the television series, the primary emphasis remains on the political tension between the Sorcerer Kingdom and the Re-Estize Kingdom, whose internal corruption and poor leadership leave it increasingly vulnerable to conflict.

The season reaches its climax when a diplomatic dispute escalates into war between the Sorcerer Kingdom and Re-Estize. After supplies belonging to Nazarick are stolen by rogue nobles, Ainz uses the incident as justification for military action. Despite attempts by several leaders to avoid bloodshed, the conflict becomes inevitable as Nazarick launches a full-scale invasion.

The Dwarf Kingdom Arc sees Ainz forge new alliances while helping reclaim the dwarves’ homeland from invading forces (Image via Madhouse)

One of the most significant battles features the overwhelming advance of Nazarick’s forces against the Re-Estize Kingdom. Led by the Floor Guardians and supported by powerful undead armies, the invasion quickly exposes the enormous gap in military strength between the two sides. Even experienced warriors and commanders struggle to mount meaningful resistance against Nazarick’s elite forces.

The season also highlights the abilities of several Floor Guardians beyond Ainz himself. Albedo continues overseeing political operations, Demiurge orchestrates strategic campaigns behind the scenes, and Cocytus demonstrates his leadership during military engagements. Together, they reinforce why Nazarick remains virtually unbeatable against any nation in the New World.

By the end of Season 4, the Re-Estize Kingdom suffers devastating losses, dramatically altering the political landscape. The destruction sends a clear message to every neighboring nation that opposing the Sorcerer Kingdom carries catastrophic consequences. At the same time, Ainz continues believing many of his achievements result from misunderstandings, while his subordinates interpret every decision as evidence of an unfathomable master plan.

Overlord Season 4 expands the franchise beyond dungeon exploration and individual battles, presenting a story driven by diplomacy, conquest, and nation-building. Combined with large-scale warfare, memorable confrontations, and continued development of Nazarick’s leadership, the season marks one of the most important chapters in Ainz Ooal Gown’s journey to dominate the New World.