|Release date||19 August 2010 (Update)|
|XP per kill||Varies|
|Examine text||A demon used to barking orders to its warriors.|
Yk'Lagor the Thunderous is the final Dungeoneering boss monster encountered on the occult floors. He is found on floors 45 to 47 of Daemonheim. A Dungeoneering level of 89 is required to fight him. He is a high-ranking Kal'Gerion demon and one of Kal'Ger the Warmonger's generals.
Unlike other bosses who are immediately ready to fight when the player enters the room, Yk'Lagor must first be freed before he can be fought; upon entrance to the boss room, Yk'Lagor is bound to the ground and surrounded by a barrier that appears to be held by several Mysterious mages in the room. After attacking four of the mages, the demon will roar "My turn!" and break free from the barrier, causing the entire dungeon to shake and killing the rest of the mages with a single, powerful blast of magic that will not target any player.
Yk'Lagor's standard melee attack involves slashing the player if the player is standing in melee-range. The demon will attack with a fire based magical attack if no players are next to him which can drain prayer points and and ignores protection prayers.
Yk'Lagor also has two powerful special attacks which he alternates between. When he uses magical drag, he shouts "Come closer" and tries to drag you after a few seconds. If he succeeds he will heal 15% of his health per player dragged in. He also stuns you for a relatively long time, drains prayer points and disables any protection prayers. The attack can be avoided by hiding behind any of the four pillars in the boss room. Yk'Lagor will always use this attack right after he is freed, so you can easily prepare to run behind the pillars. Use freedom if caught.
His second special attack is an earthquake. He will shout "This is..." before jumping into the air. When he lands he shouts "TRUE POWER" while shattering the ground. This special attack can easily kill ANYONE not hiding behind the pillars. You will have a few seconds to hide when he starts using this attack.
Yk'Lagor's boss room has different rules for teleporting than any other place inside Daemonheim. You can only use the regular Gatestone teleport or Group Gatestone teleport if you're standing behind one of the pillars, otherwise you'll receive a "You can't teleport here" message. Gatestones cannot be used to evade his special attacks.
Yk'Lagor's special attacks can be avoided by running behind a pillar as soon as the text appears above his head or you hear his voice. To successfully hide from the boss's special attacks, it is recommended for players to attack with either ranged or magic.
Apart from his special attacks, Yk'Lagor will behave in a pattern depending on how you're fighting him. As long as 1 person is close to him, Yk'Lagor will use his melee attacks. They can be partially blocked by Protect/Deflect Melee. This is a usually fast attack and can hit very hard on unprotected players.
As long as 1 person stands away from him, he will use his Magic attack, which hits everyone in the room. This is indicated by him shouting "Fear my wrath!". You will still get hit even if you stand behind a pillar, but only if he can target a player in his range, meaning if one player is not hiding behind a pillar, all players will get hit.
|Novite battleaxe||1||Random||Not sold|
|Off-hand novite battleaxe||1||Random||Not sold|
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|Off-hand bathus battleaxe||1||Random||Not sold|
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|Off-hand fractite battleaxe||1||Random||Not sold|
|Zephyrium battleaxe||1||Random||Not sold|
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|Argonite battleaxe||1||Random||Not sold|
|Off-hand argonite battleaxe||1||Random||Not sold|
|Katagon battleaxe||1||Random||Not sold|
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|Off-hand promethium battleaxe||1||Random||Not sold|
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|Off-hand primal battleaxe||1||Random||Not sold|
|Kal'gerion notes (part 4)||1||Common||Not sold|
|Mysterious chronicle||1||Common||Not sold|
- One of the phrases the mages binding Yk'Lagor The Thunderous are chanting is "Heim crabs are awesome" backwards. (This was confirmed during the Q&A session at Runefest.)
- With the addition of this boss, this is the first time voice acting has appeared in the game aside from the tutorial.
- In Yk'Lagor's concept art, it is shown that his original title was "the Vociferous", which can be understood as a synonym for "the Thunderous" (a loud or noisy scream); he was also entitled as "Demon Prince".
- Yk'Lagor introduced a trend in which his Magical Drag attack is used by many powerful monsters, not limited to Kal'Ger the Warmonger, a variation that Nex, troll wizards, and Mother Mallum all use, and its sound effects are used in the Ancient ceremonial robes emote.
- Yk'lagor used to have another special attack in which he created an area of explosions around him (similar to the ancient curse Wrath), but for some reason this was removed.
- As shown in the video from Jagex's YouTube channel, there were 4 pillars on the northern and the southern part of the room. In the actual game, there are only 2 pillars on each side.
- Currently there is a glitch where if a player dies at the same time as Yk'Lagor's magical drag special attack is used, the player may be dragged into the boss room from the start room.
- Resonance used to work on his earthquake special attack.
- Yk'Lagor is voiced by Mod Osborne.