Kal'gerion demon

Kal'gerion demons are found within the Daemonheim peninsula, in the Kal'gerion resource dungeon, requiring level 90 Dungeoneering to enter. They can be assigned as a Slayer task by Kuradal or Morvran, to players with at least level 90 Slayer, but this is not required to kill them normally.

Kal'gerion demons drop Kal'gerion battle commendations, all of which are required to unlock the trimmed completionist cape.

Strategy
Kal'gerion demons have high defence and life points. While they list no explicit weakness, magic is the most consistently hitting style. It is advisable to use protect/deflect melee/soul split when fighting them, as it will block 50% of their damage (and if you are using deflect, it will also hurt them quite a bit). Otherwise, you will have to use a lot of food to keep healing. Something to consider is using devotion as it will temporarily lower their max hit to 1. Also noteworthy is using debilitate to cut their damage output in half (use alongside protect melee). Since they are quite strong monsters, you are best off using stat-boosting potions (like extreme magic) and using prayer renewal potions.

Be wary of using multi-target attacks, as more than one demon attacking could prove problematic.

The demons can easily kill a familiar, so use provoke to resume its aggression on the player if necessary.

The demons have a special attack, which will do one of two moves randomly. They will only do this special attack once per battle. These attacks can be avoided completely by hiding behind one of the rocks scattered about the room as the demon prepares its attack. If a special attack knocks you below half health, it will not trigger portents of restoration. The special attack can be spotted early by a change in the demon's animation. During a regular attack, he will swing one arm across his chest. However he starts the special attack by instead moving both arms back together. He then either jumps or raise one arm in a 'pulling' action. During this, the demon will not attack and although the demon can be stunned normally, stuns will not cancel the special attack.


 * Drag - The demon drags its target, dealing high damage and healing itself. Players will be dealt up to 1000 damage while the demon will heal for 5062 life points. (15% of their maximum). This attack will also stun the demon's target without leaving a status icon indicating such. Freedom and Anticipation will not block this stun, because it acts like a bind, rather than an actual stun (though players still cannot attack the demon in this state). However, using Freedom will clear the effects.
 * True power - The demon jumps in the air and smashes the ground, hitting around 1,000 unblockable damage to its target.

There is a third special attack that will also be used by the demon if you hide behind a rock or move too far away. The demons can do this at any time, not only as their special attack; they can thus use it more than once per fight. It is possible for this special attack to override one of the previous two by hiding early.
 * Flame portal - The demon casts a flame portal over its target that repeatedly hits around 400-600 unblockable and typeless damage.

Trivia

 * Although their long-distance attack has a magic animation, it is classified as a melee attack. BTS 105 has also said that they use magic, but they do not. This may be an oversight from Jagex.
 * The Pummeller variant of the demon seems to lack a melee attack animation, despite the fact that Bal'lak the Pummeller has one.
 * The demons borrow techniques from Yk'Lagor the Thunderous and Har'Lakk the Riftsplitter.
 * If the player asks a Slayer master on advice on how to kill a demon, they will say that the demon is weak to stabbing attacks, despite having no weaknesses, similar to the Airut.
 * Despite being classified as demons, they are unaffected by holy water.