Pyroblast

Pyroblast is a Mage spell, acquired by specializing in the Fire tree. It deals massive fire damage with a large direct damage portion, followed by a DoT portion. It can deal more single-target damage than any other mage spell, but at a higher cast time.

Damage caused
This tables shows Pyroblast's damage for each fifth level, starting from 10 when it's obtained.

Arcane

 * Arcane Concentration gives you a 3/6/10% chance of entering a Clearcasting state after any damage spell hits a target. The Clearcasting state reduces the mana cost of your next damaging spell by 100%.
 * Netherwind Presence gives 1/2/3% spell haste.

Fire

 * Fire Specialization is given to all mages specializing in Fire. It increases the damage of all Fire-spells by 25%.
 * Flashburn (Mastery) increases the damage done by all your periodic fire damage effects by 20%. Each point of Mastery increases periodic damage done by an additional 2.5%.
 * Master of Elements Your spell criticals will refund 15/30% of their base mana cost.
 * Burning Soul reduces the casting time lost from taking damaging attacks by 23/46/70%.
 * Ignite causes your critical strikes from Fire damage spells to cause the target to burn for an additional 13/26/40% of your spell's damage over 4 sec.
 * Fire Power increases the damage of your Fire spells by 1/2/3% and gives your Flame Orb a 33n% chance to explode at the end of its duration.
 * Impact Gives your damaging spells a 3/6/10% chance to reset the cooldown on fire blast and to cause the next Fire Blast you cast to stun the target for 2 sec and spread any Fire damage over time effects to nearby enemy targets within 12 yards.
 * Hot Streak causes your spells to no longer trigger Arcane Missiles. Instead, your critical strikes with Fireball, Frostfire Bolt, Scorch, Pyroblast, or Fire Blast have a chance to cause your next Pyroblast spell cast within 15 sec to be instant cast and cost no mana.
 * Improved Hot Streak does not directly boost Pyroblast, but causes you to have a 50/100% chance to trigger your Hot Streak effect any time you score 2 non-periodic critical strikes in a row with your Fireball, Frostfire Bolt, Scorch, Pyroblast, or Fire Blast spells,
 * Combustion instantly deals X Fire damage and creates a new periodic fire effect on the target, lasting 10 sec and dealing the same damage per time as all your existing periodic fire effects.
 * Molten Fury increases damage of all spells against targets with less than 35% health by 4/8/12%.
 * Pyromaniac increases spell haste by 5/10% if 3 or more targets are taking Fire damage over time from your spells.
 * Critical Mass causes your Living Bomb and Flame Orb spells to deal more damage, and your Pyroblast and Scorch spells to have a 33/66/100% chance to cause your target to be vulnerable to spell damage, increasing a spell critical strike chance against that target by 5%. Lasts 30 sec.

Frost

 * Piercing Ice Increases the critical strike chance of your spells by 1/2/3%.
 * Shatter Multiplies the critical strike chance of all your spells against frozen targets by 2/3.
 * Talents in the Frost tree beyond Tier 1 are impossible to access due to lack of talent points.

Glyphs

 * Glyph of Pyroblast (Prime Glyph) increases the critical strike chance of your Pyroblast spell by 5%.

Tips and tactics

 * Due to the somewhat long cast time, this can be used to open battles when soloing. This is one of the few things a fire mage can do to improve his mana efficiency; this spell has better DPM than Fireball but a longer cast time. Use of Pyroblast in a group is not recommended unless the tank has sufficient threat.


 * Polymorph/Pyroblast: The standard opener of anyone who knows Polymorph, this tactic is mostly seen in PvP. It works exactly as described: Polymorph the target, then cast Pyroblast. You Polymorph first so that the target cannot deal damage or interrupt you while you cast. Keep in mind that in PvP, many people will use various abilities to prevent Polymorph, so be ready to recast it. This is also useful in PvE questing where you pull two mobs: open on one mob with Pyroblast as normal, Polymorph the additional mob, finish off the first mob, and opened on the sheeped second mob with Pyroblast.


 * The final set bonus of Netherwind Regalia gives you a 10% chance on Arcane Missiles, Frostbolt or Fireball cast to allow the next spell with casting time to be instant, just as if using the arcane-talent Presence of Mind. This gives mages without arcane talents an even better use of Pyroblast.

History
Prior to patch patch 3.0.9, this spell was part of a technique called the "three-minute mage". It combined the three spells Pyroblast, Presence of Mind and Arcane Power into an instant attack that dealt massive damage. It was famous as a nuking trick, often used in PvP. 3.0.9 caused Presence of Mind and Arcane Power to share cooldown, which somewhat softened this technique down. With the new talent system in 4.0.1, it has been completely removed from the game.

Trivia

 * A type of candy, the, is named after this spell.