The Magister

Oreb, the Magister of House Charron, is a necromancer from the human homeworld of Teragard, and a solo slayer boss. He may be found in the First Gate of the Grim Underworld, accessible from the Sophanem Slayer Dungeon. Unlike the other inhabitants of the dungeon, a feather of Ma'at is not required to kill him.

To fight the Magister, level 115 Slayer is required (which can be boosted - however, the boost must be maintained throughout the whole fight) and a Key to the Crossing. The soul obelisk inside the dungeon must then be activated to summon him. Keys can be obtained by killing the inhabitants of the dungeon (including himself) or by buying them from the Grand Exchange, costing. The key is consumed when beginning the fight and will not be returned on death if the Magister wins, behaving in a similar manner to ascension keystones.

Killing the Magister is a possible Soul Reaper assignment.

The Magister is one of the bosses required to unlock the The Reaper title, which is a requirement for the completionist cape. Obtaining the five books that can be dropped by the Magister as well as other inhabitants of the dungeon is a requirement for the master quest cape. The bobblehead pet dropped by the Magister is a requirement for the Final Boss title. Acquiring at least one of each of his unique drops is a requirement for the of the Crossing title.

History
Oreb was originally the magister of House Charron on Teragard, and at one point authored a book known as The Divine Delusion. Fascinated with the subject of the soul, he speculated in his book that it had little to do with divinity, and that it may be possible to transplant a soul from one host into another.

At some point in or before the Fifth Age, he somehow found his way to Gielinor, and took in Nomad as his pupil, teaching him about the nature of souls. Nomad eventually betrayed and killed him, using his new understanding of souls to bolster his own power. He evidently survived this, however.

Memories of him appear during the Tales of Nomad miniquest. In the first master memory, he appears as my first master and is shown tutoring Nomad in the Ourania Cave. In the first betrayal memory, he is shown being stabbed by Nomad in his temple.

After being betrayed by Nomad, Oreb eventually found himself in Menaphos. He began his own experiments on souls, taking pity on Icthlarin because of a guilt that he sensed. He found various machines capable of splitting a being's soul while they were still alive, and also sensed the soul of a divine being, though it had clearly been split into multiple personalities.

In his last journal, he notes that his experiments have attracted the player, which he interprets as a success.

Strategies
The Magister has several special abilities, one of which consists of summoning a soul obelisk that drains the player's Constitution level, which affects both the amount of health food can heal when eaten in addition to the player's maximum life points.

The slayer helmet will not apply its damage and accuracy buffs against the Magister, even though he counts towards a soul devourer task.

Pre-release
There were several teasers hinting towards the Magister in the weeks before its release. Most of them have taken the form of in-game messages which were triggered as a result of the players' actions as a community.

After several teaser message broadcasts, more activities were unlocked for players to engage with within Menaphos that allowed city reputation to be gained in ways beyond the traditional method of training skills within the city. These activities took the form of repeatable events that could be completed numerous times a day for reputation, and are still currently available to be completed for city reputation.

The Magister was originally planned for release on 26 June 2017, but this date was pushed back to 3 July 2017 to allow for further testing and addition of more quality of life improvements for Menaphos.

Trivia

 * Upon release, there was a bug where the Magister gave 50,000 slayer experience upon defeating him. This was unintentional and quickly hotfixed on the same day, reducing it to 8,000.
 * The title "Magister", when translated idiomatically from Latin, means "Master" - a honorific title often used to address individuals of high social status, such as teachers.
 * The Magister is one of two monsters who can lower the player's maximum life points, the other being Barrelchest Mk II.
 * It was possible to Quick Chat Magister kills before the boss was actually released.
 * He is referred to as High Magister Oreb by Lucifurr, who claims to have been his apprentice.
 * Upon release, there was a rare bug that caused the Magister to become immune to most forms of damage at low health, forcing the player to kill him off with weapon poison. He could still attack and damage players, but was incapable of using abilities. This has been fixed as of the 10 July 2017 update.
 * The Magister was given the ability to use Freedom against stuns with the 23 July 2017 update. Prior to this, he would only use Freedom if he was bound.
 * The Magister was given several updates due to player complaints on 2 October 2017:
 * His overall defence was lowered; this applied to both his defence level and his affinities, as they were extremely low compared to other bosses, often requiring the use of an aura just to sustain reasonable accuracy rates.
 * He is now able to phase whilst stunned.