Improved Shatter
Shatter damage has a 50% increased chance to critically strike.
Tree position
In the Frost Mage talent tree, Improved Shatter sits in the Frost specialization talents, row 7 of 11. It is a single-point node. Its row opens once 8 points are spent in Frost Talents.
Connected above
The tree draws a line into Improved Shatter from Splintering Ray or Frigid Focus and Flash Freeze.
Splintering RayRay of Frost deals 30% of its damage to 5 nearby enemies.
Frigid FocusRay of Frost damage increased by 30%.
Flash FreezeCasting Glacial Spike has a 100% chance to grant you Fingers of Frost.
Connected below
Improved Shatter leads on to Glacial Attunement and Heart of Ice.

Heart of IceIce Lance Shatters 1 additional stacks of Freezing.
Same row
Also on this row: Fractured Frost, Deep Shatter and Wintertide or White Out.
Fractured FrostIce Lance strikes 1 additional targets at 50% effectiveness, preferring enemies with more stacks of Freezing.
Deep ShatterShatter's critical strike damage is increased by 50% of your critical strike chance.
WintertideFrozen Orb has a 100% chance to grant Brain Freeze.

Talent trees
Improved Shatter is in the talent tree of 3 specializations. Mage: Arcane (DPS), Fire (DPS), Frost (DPS).
Improved Shatter Changes by patch
Tracked changes to this talent between game data builds, newest first.
- First tracked in the game data (patch 12.1.0)