Molten Furnace
The party first meets Braham and Rox preparing to infiltrate the Molten alliance Weapons facility. Speak to Rox to start the drill.
Ambush
After talking to Rox a portal will open and an ambush of enemies will appear. After defeating them a Molten Brawler will appear which you’ll need to also kill. once dead you can proceed into the tunnel dug by the drill.
Tunnel
The drill will begin tunneling through and you’ll have 5 sections to dip into before reaching the end. Each section will have a group of enemies that need to be killed and a blocked steam geyser that needs to be destroyed or a steam geyser that has to be blocked with a nearby boulder. Each section also has one mithril ore node.
Crowd-Control with pulls helps in rounding up mobs for better cleave.
Standing too close to the drill will cause 
Burning
AegisA large group of molten enemies awaits you at the end of the tunnel. Destroy them and move forwards to a steam wall. There will be multiple steam walls to pass through, wait until the steam wall stops for a few moments before going through.
Traverse down some rocks into the final chamber where you’ll encounter the main boss.
Weapons Testing Facility
Engage the Weapons Test Engineer and in the Weapons Testing Facility, this is a multi-phase encounter.
Enter the arena and 2 champions will spawn a Protector Sentinel Suit and a Nimble Sentinel Suit they fixate on the closest player. If the two suits get close to each other they will gain a buff called 
Sentinel Retribution that damages any player that hits them, so split them up and defeat them. While fighting them the fireball mechanic will be happing.
Once the Suits are dead Veteran Molten Shamans will spawn around the core and the core itself will become vulnerable and begin venting flame that does damage. The core will stop taking damage around 50%, and any leftover shamans will leave. While damaging the core the shockwave mechanic will be happing.
After the core stops taking damage the two champions suits from before will spawn again. While fighting them the fire tornadoes mechanic will be happing.
After the suits are defeated more Veteran Molten Shamans will spawn and the core will become vulnerable again. burn it down. Around 25% the leftover shamans will leave but the core will remain vulnerable bur fire all the arena mechanics at once until it’s destroyed
The arena has three mechanics by itself.
Fireballs
Multiple fireballs will be shot in a pattern covering a section of the room, placing down red circles that ignite with burning. Avoid these by standing in the safe zones for each barrage shot of fireballs, they can also be reflected.
Shockwaves
Each corner of the room has a stomper hanging above it. When dropped, it creates a shockwave that knocks you down. use 
Stability
Fire Tornadoes
Multiple fire tornadoes will spawn on one side and travel across the room to the opposite side of their spawn. You can dodge, use Stability
Weapons Test Engineer
Once the thermal core is destroyed, the Weapons Test Engineer will join the fight including the 2 champions suits seen before. The Weapons Test Engineer will also gain Sentinel Retribution if a suit is too close. So defeat the 2 champions (separately) and DPS the boss. The boss will gain invulnerability every 25% and pick 1 of 4 random locations to tunnel to (it may not move at all and engage where it was initially phased), up to three Veteran Molten Shamans (based on fractal tier) will also spawn. Be sure to observe the spot the boss will tunnel to get an early start on dealing damage.
