When he learns that the Prophets' plans would doom all sentient life in the galaxy, the Arbiter allies with the Covenant's enemies (humans) and stops the ringworld Halo from being activated.

A different Arbiter, Ripa 'Moramee appears in the 2009 real-time strategy game Halo Wars, which takes place 20 years before the events of the main trilogy.

[2] Staten said that the purpose of introducing the Arbiter was "to offer another, compelling point of view on a war where telling friend from foe wasn't always clear-cut.

[3] While there were those in Bungie who were against the Arbiter as a player character, Staten chalked its inclusion in the game to a combination of wearing down his opponents and the gameplay sandbox opportunities that came from having Covenant allies.

The only substantial difference between the Arbiter and other Elites was special ceremonial armor, which appeared in early concept sketches as part of the character's final design.

However, as Tom Edwards, a consultant who worked with Microsoft during the review noted, "within the game's context this Islamic-related name of 'Dervish' set up a potentially problematic allegory related to Halo 2's plot—the [United States]-like forces (Master Chief/Sarge) versus Islam (the religious Covenant, which already had a 'Prophet of Truth' which is one title for Muhammad)".

Previously a commander in the Covenant military, he is shamed for failing to stop the human soldier Master Chief from destroying the Forerunner ringworld Halo (as depicted during the events of Halo: Combat Evolved); the Covenant revere the Forerunners as gods and believe the rings are the key to the salvation central to their religion.

[12][13] As a playable character, the Arbiter was identical to the Master Chief, save for the replacement of a flashlight with an active camouflage system.

[16] Thel 'Vadam reappears in Halo 5: Guardians, where his forces, the Swords of Sangheilios, remain locked in combat with a faction of Covenant on Sanghelios.

[20] Parts of the Arbiter's backstory before the game's events are explained in a tie-in graphic novel, Halo Wars: Genesis.

[22][23] An Arbiter makes a non-canon appearance as a guest playable character in Killer Instinct: Season Three, voiced by Ray Chase.

He uses several weapons from the Halo series in combat, and fights in the Arena of Judgment, a stage set in the midst of a battle on Sanghelios.

[34][14] Alternatively, publications like GameSpot thought that while the Arbiter and Covenant side added "newfound complexity to the story", it distracted the player from Earth's fate.

Hilary Goldstein of IGN decided the change took away the "intriguing side-story of the Arbiter and his Elites", in the process reducing the character's role to that of "a dude with a weird mandible and a cool sword".

[41] Goldstein took issue with the poor artificial intelligence of allies in the game and singled out the Arbiter in particular, describing the character as useless.

[44] On the opposite end of the spectrum were reviewers like G4tv, who argued that the Arbiter was more likeable, not to mention more useful, as an AI sidekick instead of the main player.

[47] Halo Wars's cinematics and voice acting were widely lauded,[48][49][50][51] although one reviewer wrote that the characters were stereotypical and unlikeable.

"I'd much rather experiment and do something surprising, and not have everybody appreciate it, than just turn the crank and do another alien war movie with a space marine," said Halo 2 design lead Jaime Griesemer.

Community lead Brian Jarrard attributed some of the fan backlash to a discord between the game's marketing and the actual gameplay.

"I think, even more so than playing as the Arbiter, the thing that people were disappointed with and angry about is that they were promised this experience, through the marketing, of being really backs against the wall, Earth's under siege, we're going to do all we can to save our home planet...

Referring to Halo 2's cliffhanger ending, Griesemer said, "I think if we'd been able to finish that last couple of missions and get you properly back on Earth, a lot of the reaction would have been placated.

In 2021, a Polygon article stated "the Arbiter gives Master Chief a run for his money as "badass video game protagonist", and he does it in only six missions.