The game tells two different, albeit similar, stories involving the same two protagonists; Valens (the son of one of the greatest gladiators the world has ever known) and Ursula (the adventure-craving, magic-infused daughter of the barbarian king).

In each storyline, the protagonists form a school of gladiators to compete at regional games but soon find themselves facing a potentially world-ending event when an evil sorceress sets out to resurrect the Dark God Mortuus, who once brought the world to near-ruin.

[27] As well as facilitating travel, the world map also features merchants who sell items not available in the regular shops, and NPCs to whom the player can speak, possibly getting side quests, hints, or local history.

Unlike in many games with multiple player characters, the two campaigns in Gladius do not present different perspectives on the same story.

[a] The game takes place in the fictional lands of Gladius where, decades earlier, only the barbarians of Nordagh stood against the marauding Empire of Imperia.

[32] The ensuing conflict, known as the Great War, was vicious and bitter, and although it quickly reached a military stalemate, the slaughter senselessly continued.

So pronounced was the violence that it led to the rebirth of the Dark God, Mortuus, a dragon-like entity who began to lay waste to both armies.

In response, the benevolent Affinity Gods lent their strength to Galltyr, Queen of the Valkyrie, and with her Warriors of Light, she attacked Mortuus.

The few human survivors vowed never to allow something like this to happen again, and Imperia withdrew from Nordagh, with a temple built over the body of Mortuus, sealing in his evil.

As the game begins, Valens and his father, Munio (regarded as the greatest living gladiator), are returning from the amphitheatre when they are attacked by a group of men.

Eventually, the increasingly antagonistic Ludo leaves the school, accusing Valens of lacking ambition and disgracing Munio's legacy.

The only way to defeat Mortuus is for Valens to combine his powers with those of Ursula, with whom he has fallen in love, and who is revealed to be a descendant of the Valkyrie.

[41] In an undisclosed location, Nyphelia receives a report telling her that despite the setback in Roanor, Nordagh has fallen, and "soon all nations shall tremble as our army marches across the land."

In Nordagh, twenty years before the game begins, the Galdr witches, prophesize that Mortuus will return with the aid of a young girl.

They meet with the High Priestess, who states, "sisters, we have read the prophecy wrong; she does not only bring about the coming darkness.

[41] In an undisclosed location, Nyphelia receives a report telling her that despite the setback in Roanor, Nordagh has fallen, and "soon all nations shall tremble as our army marches across the land."

[6] The press release emphasised the two storylines, the mixture of single-player and multiplayer modes, and the core game mechanic of building up and managing a gladiatorial school.

LucasArts estimated that it would take around 72 hours to complete both storylines, emphasising the size of the game's four distinct regions.

Besides signaling LucasArts' return to original game development, Gladius features a distinct style of play that is wrapped in an epic storyline.

In terms of influence, Blackadder cited Final Fantasy Tactics, Vagrant Story, Madden NFL 2002, Mario Party, and "lots of RPGs.

[48] According to Q&A lead, Chuck McFadden, the team constantly sought to push things; "[we] wanted to take this game genre farther than anyone else has.

[50] The game also features fantastical elements, such as gods and magic, and additional non-human classes such as Valkyrie, yetis, undead, satyrs, cyclopes, ogres, and minotaurs.

To that end, there were individual programmers working specifically on each version with their primary role being to ensure that the game takes advantage of each platform's architecture, all while maintaining a constant 60-frames-per-second frame rate across all three consoles.

[51][52][53] Game Informer's Matthew Kato scored the GameCube version 9 out of 10 and was especially impressed with the depth of the combat mechanics, particularly lauding the implementation of the hit meters.

"[55] Also writing for Game Informer, Andrew Reiner scored the PlayStation 2 version 9 out of 10, calling it "a compelling and ingenious romp."

"[56] Jeremy Zoss scored the Xbox version 9.3 out of 10, also praising the range of customisation, the depth of the combat mechanics, and, especially, the hit meters.

Although he found the pace "sluggish", and the graphics under-par, he praised the simplicity of the gameplay, the implementation of hit meters, and the depth of customisation, calling it "one of the deepest games of the year.

"[65] GameSpot's Greg Kasavin scored all three versions 8.4 out of 10, writing "Gladius [is] not just a great game but, in certain ways, a pioneering one."

He was critical of the plot and some of the graphics, but felt "there's a lot to love", arguing "its shortcomings are minor [and] weaknesses are swept away by the sheer size and depth.

Joe Fielder scored it 6 out of 10, praising the characters and storyline, but was critical of the pacing; "if the number of battles were cut by at least a third and its combat speed doubled, the game could be on track for star status."