The fight with Razorscale begins in the air. Razorscale has two abilities while she's flying around: Devouring Flame and Fireball. You'll need to kill some waves of Runeforged Adds while defending yourself against her air attacks. The Dwarfs will be busily repairing the turrets while all of this is going on. A player can use these turrets to bring her closer to the ground and after 4 have been used she will fall to the ground and allow your raid to finally do some damage. This will continue until Razorscale reaches 50% health. From then on, she will fight you on the ground. The idea here is to get her to 50% before she takes off for the second time as you can only allow her to fly off once. Use your Bloodlust/Heroism, Trinkets or any other abilities to increase your DPS when she's on the ground.