|Royal Prince Marshal|
|Name||Royal Prince Marshal|
|Hair color|| Blonde (anime, Akira Ishida)|
Brown (light novel, Asami You)
Royal Prince Marshal is known for his intellect and skill in leading armies. According to the Holy King, the only reason he could keep up with Young Merchant's implications was because he had a "smarter younger brother."
Despite standing in opposition to the main characters, Royal Prince Marshal isn't particularly villainous. His primary motivation for participating in the Holy Key Expedition is first, because of the Archbishop's orders, and secondly, to ensure the safety of the Holy Kingdom's citizens and thus the rest of Central. When Older Sister Maid confronts him in the Demon World with her human army, she successfully convinces him to back down from invading the Blue Demons territory (with Hero's backing). Later, when she reveals the Ball of Light, which was the Church's Holy Relic that they had started this Expedition for, he agrees to a ceasefire and peace treaty since they no longer had a reason to fight.
However, he is also unafraid to use violence in order to achieve his goals or gain an advantage. During the attack on the Southern Union, he manages to capture a blacksmith from the Iron Kingdom who was taught how to make a gun by the Crimson Scholar. Royal Prince Marshal obtains the information on how to make it through torture, and then wastes no time in having it mass-produced so that they would have an advantage in the Holy Key Expedition.
Attack on the Southern UnionEdit
Third Holy Key ExpeditionEdit
Royal Prince Marshal is a skilled tactician and has a good grasp on waging war. Although he has no special powers, he is briefly able to stand his ground against Female Knight and exchange blows with her. Generally, however, he doesn't take to the front lines himself.
Older Sister Maid: Older Sister Maid and Royal Prince Marshal confront each other only twice in the series, but those are also two of the biggest turning points of the war. The first time, she convinces him (with Hero's help) to turn around and return to the main army without taking over the Blue Demons' territory. By successfully stopping his army, she is rewarded the Ball of Light, which was the Holy Relic that the Holy Key Expedition claimed to be fighting for. As a result, when she presents it to Marshal in front of both armies, he has no choice but to accept it, along with a ceasefire and peace treaty.
Royal Prince Marshal respects her as a "warrior" even though she is a noncombatant. At the same time, though, because she willingly entered the battlefield, he also had no compunctions about using violence to get his way. Nevertheless, he and the Chief Strategist think of her highly enough to misinterpret Hero's words about her to mean that she was the Crimson Scholar, and believe it.
Archbishop: Royal Prince Marshal is fully aware of the Archbishop's manipulative nature, scoffing at the pretense of a "holy war," although he does nothing to fight it. However, he gradually becomes more and more fed up with the Archbishop's haphazard "strategy," which would lead the army to ruin.
Blue Ash King: The two heroes of Central have a good relationship, holding a strategic meeting together at the end of the unsuccessful invasion of the Southern Union in the Akira Ishida adaption. Later, Royal Prince Marshal takes the Blue Ash King's suggestion on how to more effectively utilize their musketmen.
While the Blue Ash King is more eager for war, he is also more honorable, which is suggested when he was unaware of the White Night Kingdom's attempted ambush, and Royal Prince Marshal hides this fact from him. Furthermore, the Blue Ash King disliked the idea of non-combatants following the Holy Key Expedition, but Royal Prince Marshal reminds him that they were necessary for waging war.
As the expedition went on, Marshal found himself in conflict with the Church; and the Blue Ash King, having been seduced by the Lily Knight Captain, sided with the Church. Because of this, Marshal splits from the main army to secure supplies from the Blue Demon territory, while the main army led by the Blue Ash King attacked Gateway City. After this, the two never meet before the Blue Ash King is killed, in spite of Marshal's attempts to contact those in charge of the main army.
- His voice actor, Takahiro Sakurai, would go on to voice Krusty in Mamare's next series, Log Horizon.