This is the first boss encounter in the Liberation of Undermine Raid.

This is a two-phase boss encounter that involves removing the Protective Plating off of Vexie's Wartank, The Geargrinder, to trigger a Mechanical Breakdown. The phase transition occurs once all Protective Plating is removed and the fight will alternate between these two phases until it is defeated. 

Following this fight, raiders can choose to continue on to one of 4 bosses (Cauldron of Carnage, Rik Reverb, Stix Bunkjunker or Sprocketmonger Lockenstock).  All four of these bosses may be defeated in any order, but must be killed before moving on to the 6th boss, One-Armed Bandit.

Tactics

Phase 1

• Boss starts with 4 Protective Plating stacks - break all within 2 mins.

• Kite around the edge.  DPS from the front.

• Red lines - bikers - bait towards boss.  Then people get onto bikes, aim at boss and fire (button 1).  This reduces boss's armour plating.

• Tanks swap on Tankbuster.

• Large purple circles - move out (drops oil in heroic).  

• Boss also poops oil out (Heroic).

• Incendiary Fire - Mid-sized fire circles can be placed on oil to remove it.

• Once stacks are down, enter Phase 2.

Phase 2

• Boss takes double damage for 45 seconds.  Bloodlust.

• Healers - raid wide damage.

• Adds appear casting "repair" which will reduce the double damage phase. CC/interrupt.  They will disappear at end of phase.