Yellow swirls appear, then spikes erupt from them, dealing 1.9 million fire to anyone hit. These are used to mitigate other mechanics, so the idea is to keep them up until needed.
Spoiler: Infernal SpikeShow
One player gets targeted with a red arrow, then six seconds later gets a star hurled at them, dealing 5.5 million fire to the raid. Damage decreases every Infernal Spike the star passes through. If it passes through no Infernal Spike, the target suffers 6.6 million fire a second for 12 seconds. Anyone hit by the star while it travels takes 1.6 million fire.
Spoiler: Shattering StarShow
Goroth channels then deals 8.2 million fire to anyone not behind an Infernal Spike. Any player hit receives a DoT that deals 3.3 million magic every 2 seconds for 10 seconds.
Spoiler: Infernal BurningShow
3 players get targeted with yellow swirls, then a comet crashes on them, dealing 1.3 million fire within 10 yards of impact. Anyone hit takes 1.6 million fire every 2 seconds for 16 seconds. These destroy Infernal Spikes, so targets must make sure not to hit any player or pillar.
Spoiler: Crashing CometShow
A quarter of the room gets covered with fel, destroying any Infernal Spikes. Fel deals 608,000 fire every second. The idea is to have your range relatively spread around the room so you don't lose all your pillars.
Spoiler: Fel EruptionShow
Burning Armor/Melted Armor (TANK)
Current tank gets a big yellow circle under them. Deals 2.4 million fire every 2 seconds for 6 seconds, then explodes for 3.3 million fire more, also killing any Infernal Spikes within the circle. Also applies Melted Armor to anyone hit, which increases all damage taken by 300%. Affected tank must make sure not to hit any players or pillars. Swap immediately on application.
Spoiler: Burning Armor/Melted ArmorShow