Kael'thas Sunstrider Challenge Boss Guide for Trial by Felfire

Kael'thas Sunstrider starts with 60 Health and 2 Mana Crystals. It uses a fairly typical Spell Mage deck including powerful cards like Font of Power and Incanter's Flow. The boss's Pyromancy Hero Power will also trigger every time he plays a spell. Once the boss reaches 10 Mana, it will quite consistently use 2 Pyroblasts directly at your face for 20 damage and will play a Pyroblast on most turns thereafter.

Due the large amount of burn damage from the boss, having access to large amounts of healing or Armor is essential. Additionally, your deck must also have a win condition present as the boss will never reach fatigue damage due to Pyromancy.

For the first 6 turns of the encounter, you can be quite passive. The boss uses a deck that is largely full of removal spells, so playing any minions will only help it out. Once the boss reaches 10 Mana, it will nearly always use double Pyroblast on your face. This means that on Turn 7, when the boss has 9 Mana, you can freely setup minions on the board for the following turn. Additionally, you should also have a way to overcome the impending 20 damage, either by having large amounts of Armor or by having lots of healing ready to use. If you can successfully survive the two Pyroblasts, the boss will begin using its Pyroblasts to clear the board. From this position, you simply need to maintain enough Health to not die from Pyroblasts and enough of board to not be cleared by a Pyroblast. Once in this position, it should be easy to close out the game as the mass Pyroblasts prevent the boss from drawning more meaningful cards.

Cheap Kael'thas Sunstrider Priest