Inferno

Inferno is a solo minigame similar in fashion to the TzHaar Fight Caves that was added to Old School Runescape on the 1 June 2017, along with an update to the city of Mor Ul Rek. In order to access the Inferno, players must give TzHaar-Ket-Keh a fire cape. This is a one-time fee, so after giving a fire cape to him, TzHaar-Ket-Keh will allow players to enter as much as they want. It should be noted that purple sweets cannot be consumed in the Inferno.

According to TzHaar-Ket-Keh, he explains that the Inferno was originally a large incubation pool for newly hatched TzHaar to regain memories of their ancestors. The TzHaar found out that the deeper they placed the eggs, the TzHaar emerging from them would gain memories and knowledge of their old ancestors. Unfortunately, they went too far and completely drained the lava, finding an ancient incubation chamber. They decided to place eggs in there, but it completely backfired and caused the creation of new, volatile TzHaar creatures that were extremely aggressive and fought for dominance. The TzHaar struggle against these new monsters and are hesitant to allow JalYt to tackle them.

Logging out during waves will save your progress similar to the fight caves.

Monsters
There are new monsters encountered in the Inferno. Several of these monsters are similar to Fight Caves counterpart, while others are completely new.

Wave Breakdown
Each wave displays which monster will spawn. There are 69 waves in total. From waves 1 to 66 are three pillars which the Jal-Nibs attempt to destroy. Any remaining pillars by the end of wave 66 are automatically destroyed by the start of wave 67.
 * Wave 1.) 3x Nibbler, 1x Bat
 * Wave 2.) 3x Nibbler, 2x Bat
 * Wave 3.) 6x Nibbler
 * Jal-Ak (Blob) will start to appear in the next round.
 * Wave 4.) 3x Nibbler, 1x Blob
 * Wave 5.) 3x Nibbler, 1x Bat, 1x Blob
 * Wave 6.) 3x Nibbler, 2x Bat, 1x Blob
 * Wave 7.) 3x Nibbler, 2x Blob
 * Wave 8.) 5x Nibbler
 * Jal-ImKot (Melee) will start to appear in the next round.
 * Wave 9.) 3x Nibbler, 1x Melee
 * Wave 10.) 3x Nibbler, 1x Bat, 1x Melee
 * Wave 11.) 3x Nibbler, 2x Bat, 1x Melee
 * Wave 12.) 3x Nibbler, 1x Blob, 1x Melee
 * Wave 13.) 3x Nibbler, 1x Bat, 1x Blob, 1x Melee
 * Wave 14.) 3x Nibbler, 2x Bat, 1x Blob, 1x Melee
 * Wave 15.) 3x Nibbler, 2x Blob, 1x Melee
 * Wave 16.) 3x Nibbler, 2x Melee
 * Wave 17.) 5x Nibbler
 * Jal-Xil (Ranger) will start to appear in the next round.
 * Wave 18.) 3x Nibbler, 1x Ranger
 * Wave 19.) 3x Nibbler, 1x Bat, 1x Ranger
 * Wave 20.) 3x Nibbler, 2x Bat, 1x Ranger
 * Wave 21.) 3x Nibbler, 1x Blob, 1x Ranger
 * Wave 22.) 3x Nibbler, 1x Bat, 1x Blob, 1x Ranger
 * Wave 23.) 3x Nibbler, 2x Bat, 1x Blob, 1x Ranger
 * Wave 24.) 3x Nibbler, 2x Blob, 1x Ranger
 * Wave 25.) 3x Nibbler, 1x Melee, 1x Ranger
 * Wave 26.) 3x Nibbler, 1x Bat, 1x Melee, 1x Ranger
 * Wave 27.) 3x Nibbler, 2x Bat, 1x Melee, 1x Ranger
 * Wave 28.) 3x Nibbler, 1x Blob, 1x Melee, 1x Ranger
 * Wave 29.) 3x Nibbler, 1x Bat, 1x Blob, 1x Melee, 1x Ranger
 * Wave 30.) 3x Nibbler, 2x Bat, 1x Blob, 1x Melee, 1x Ranger
 * Wave 31.) 3x Nibbler, 2x Blob, 1x Melee, 1x Ranger
 * Wave 32.) 3x Nibbler, 2x Melee, 1x Ranger
 * Wave 33.) 3x Nibbler, 2x Ranger
 * Wave 34.) 5x Nibbler
 * Jal-Zek (Mage) will start to appear in the next round.
 * Wave 35.) 3x Nibbler, 1x Mage
 * Wave 36.) 3x Nibbler, 1x Bat, 1x Mage
 * Wave 37.) 3x Nibbler, 2x Bat, 1x Mage
 * Wave 38.) 3x Nibbler, 1x Blob, 1x Mage
 * Wave 39.) 3x Nibbler, 1x Bat, 1x Blob, 1x Mage
 * Wave 40.) 3x Nibbler, 2x Bat, 1x Blob, 1x Mage
 * Wave 41.) 3x Nibbler, 2x Blob, 1x Mage
 * Wave 42.) 3x Nibbler, 1x Melee, 1x Mage
 * Wave 43.) 3x Nibbler, 1x Bat, 1x Melee, 1x Mage
 * Wave 44.) 3x Nibbler, 2x Bat, 1x Melee, 1x Mage
 * Wave 45.) 3x Nibbler, 1x Blob, 1x Melee, 1x Mage
 * Wave 46.) 3x Nibbler, 1x Bat, 1x Blob, 1x Melee, 1x Mage
 * Wave 47.) 3x Nibbler, 2x Bat, 1x Blob, 1x Melee, 1x Mage
 * Wave 48.) 3x Nibbler, 2x Blob, 1x Melee, 1x Mage
 * Wave 49.) 3x Nibbler, 2x Melee, 1x Mage
 * Wave 50.) 3x Nibbler, 1x Ranger, 1x Mage
 * Wave 51.) 3x Nibbler, 1x Bat, 1x Ranger, 1x Mage
 * Wave 52.) 3 xNibbler, 2x Bat, 1x Ranger, 1x Mage
 * Wave 53.) 3x Nibbler, 1x Blob, 1x Ranger, 1x Mage
 * Wave 54.) 3x Nibbler, 1x Bat, 1x Blob, 1x Ranger, 1x Mage
 * Wave 55.) 3x Nibbler, 2x Bat, 1x Blob, 1x Ranger, 1x Mage
 * Wave 56.) 3x Nibbler, 2x Blob, 1x Ranger, 1x Mage
 * Wave 57.) 3x Nibbler, 1x Melee, 1x Ranger, 1x Mage
 * Wave 58.) 3x Nibbler, 1x Bat, 1x Melee, 1x Ranger, 1x Mage
 * Wave 59.) 3x Nibbler, 2x Bat, 1x Melee, 1x Ranger, 1x Mage
 * Wave 60.) 3x Nibbler, 1x Blob, 1x Melee, 1x Ranger, 1x Mage
 * Wave 61.) 3x Nibbler, 1x Bat, 1x Blob, 1x Melee, 1x Ranger, 1x Mage
 * Wave 62.) 3x Nibbler, 2x Bat, 1x Blob, 1x Melee, 1x Ranger, 1x Mage
 * Last appearance of Jal-MejRah (Bat).
 * Wave 63.) 3x Nibbler, 2x Blob, 1x Melee, 1x Ranger, 1x Mage
 * Last appearance of Jal-Ak (Blob).
 * Wave 64.) 3x Nibbler, 2x Melee, 1x Ranger, 1x Mage
 * Last appearance of Jal-ImKot (Melee).
 * Wave 65.) 3x Nibbler, 2x Ranger, 1x Mage
 * Wave 66.) 3x Nibbler, 2x Mage
 * Any remaining pillars collapse at the end of the wave and do 49 damage if you're one block away from it.
 * Wave 67.) 1x Jad 5x lv141 healers spawn when JalTok-Jad is at half health
 * Wave 68.) 3x Jad 3x lv141 healers spawn when each JalTok-Jad is at half health
 * Last wave before TzKal-Zuk.
 * Wave 69.) 1x TzKal-Zuk
 * Small waves of 1x Rangers & 1x Mages spawn periodically throughout the round.
 * 1x Jad (with 3x healers) spawns when TzKal-Zuk is at 480 HP.
 * 4x Jal-MejJaks (Zuk's healers) appear when TzKal-Zuk is at 240 HP.

Rewards
Once players manage to defeat TzKal-Zuk, they will be rewarded with the infernal cape. Tokkul is also given, with increasing amounts based on the wave they were defeated on (16,440 maximum; this is doubled if the player has completed the elite tier of the Karamja Diary).

There is also a 1/100 chance of receiving a Jal-nib-rek pet upon defeating it. Outside, players may give TzHaar-Ket-Keh any unwanted infernal capes for a second chance at a Jal-nib-rek, having also a 1/100 chance.

Trivia

 * Upon release, Jagex started a competition where the first three players to obtain an Infernal cape would be rewarded. The first player to obtain it would get a real-life version of the Infernal cape, a RuneFest 2017 ticket & travel, and lifetime membership. The second player would get the same as the first player barring the real-life Infernal cape. The third player would get a RuneFest 2017 ticket and lifetime membership.
 * Woox was the first player to complete the Inferno.
 * Kelvino was the second player to complete the Inferno.
 * Cpl Erik was the third player to complete the Inferno.
 * The name of this Minigame might be a reference to "The Inferno," the first of three books in Dante Alighieri's Divine Comedy. The main character advances through Hell's various circles (compared to Waves in the Minigame) and finally encounters Lucifer (in this case, TzKal-Zuk).