In its Hero of Many Battles form, Zacian looks like a large cyan wolf with yellow eyes, an orange tail, and orange braids going down the side of its body. Two orange fringes of fur are present on its back. Battle scars are visible on its sides, and part of one ear is missing; this ear is healed when it assumes the Crowned Sword form. In its Crowned Sword form, the fringes of fur on its back become wing-like armor and its braids grow to resemble ribbons. Additionally, its head is covered by a golden helmet, and it carries a golden sword decorated to resemble Zacian's colors.
According to legends, Zacian is believed to be either the elder sister or rival of Zamazenta. It is also known as the Fairy King's Sword by friends and foes due to it cutting down anything in one strike. It can turn itself into a statue in order to slumber until need and is capable of flying. When together with Zamazenta it can negate the power of Eternatus, even in its Eternamax State. By absorbing the metal particles in the land, it can change its form. It can also cast illusions including a projection of itself even when asleep.
Zacian can attack so gracefully the movements can captivate its opponents, which has been compare to a graceful dance. The sword it holds in its mouth can cut through anything with a sharp edge capable of harming even the thick scales of Dragon-type Pokémon as if they were just paper. When Zacian slashes its opponents it moves faster than the blinking eye, thus those struck down by its sword will not feel the pain until they fall down. When using its signature move, it can cut the ocean in two. Zacian can sheathe its sword when not in use by wrapping it with its mane.
Zacian is the only known Pokémon capable of using Behemoth Blade.
In the games
Pokémon Master Sword & Mirror Shield
Zacian appears in Pokémon Master Sword & Mirror Shield with a new Master Form equipping a stronger sword and having a new ability that prevents its stats from being lowered.