Gallade is a white, bipedal, bishōnen-like Pokémon. Its lower body consists of rounded hips with strong legs. It has a thin green torso with sharp, red horns sticking out of its chest and back. Its arms resemble tonfas with extendable, blade-like elbows. Its head resembles a gladiator's helmet with a white face, red eyes, and a teal head crest. It has spikes on the sides of its face.
It is a master of courtesy and swordsmanship capable of predicting its foe's moves, allowing it to strike preemptively. True to Gallade's honorable warrior image, it is just as protective of its Trainer as its counterpart, Gardevoir, using the blades on its elbows to defend. The shoulder blades are said to be sharper than even the best swords. Gallade is known to be sharply aware of a person's wish for help and seeks out those who need its assistance in battle, fighting savagely with fast and fierce attacks. It is capable of teaching itself swordsmanship at an impressive rate. This Pokémon inhabits mountainous areas. In Generation IX, Teleport is its signature move.
As Mega Gallade, its entire body becomes white, save for its head. Red plates emerge from its arms, its blue head crest grows slightly longer, and the spikes on its head are elongated. It also gains two cape-like protrusions on its back, giving it a knightly appearance. When the situation demands it, Mega Gallade can use its psychic power to reshape both arms into blades simultaneously and fight using a dual-wielding style. Iron Valiant bears a resemblance to Mega Gallade.
Gallade is the only Pokémon introduced prior to Generation VIII to have Sharpness as an Ability, the only Pokémon with Sharpness to not have it in a game that features Abilities, and the only Pokémon to have Sharpness as a non-Hidden Ability.
The single fin on Gallade's head resembles the helmet worn by murmillo-class Roman gladiators, or the Corinthian helmet with a horsehair crest worn by Greek hoplites, but it may also be based on medieval knights. Additionally, its battle stances in various media resemble the en garde position and parries of modern fencing, while the elbow swords themselves have a close resemblance to tonfas, wooden bars held against the arm to act as batons and arm guards. Mega Gallade's cape is similar to a matador or bullfighter's fabric.
Gallade may be a combination of gallant and blade.
Erureido may be a combination of elbow or earl, and blade. It may also involve 居合道 iaidō, a Japanese martial art of responding to attacks with swift swordplay.