Impetus

In the Arcane Mage talent tree, Impetus sits in the Arcane specialization talents, row 7 of 11. It is a single-point node. Its row opens once 8 points are spent in Arcane Talents.

Connected above

The tree draws a line into Impetus from Expanded Mind.

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  Expanded Mind

  Casting Arcane Blast or Arcane Pulse grants 2 stacks of Arcane Salvo. Casting Arcane Orb grants 1 stacks of Arcane Salvo. Casting Prismatic Bolt grants 4 stacks of Arcane Salvo.

Connected below

Impetus leads on to Illuminated Thoughts.

• 
  Illuminated Thoughts

  Clearcasting has a 3% increased chance to proc.

Same row

Also on this row: Consortium's Bauble, Arcane Tempo, Aether Attunement, Aegwynn's Technique or Arcane Echo and Resonance.

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  Consortium's Bauble

  Reduces Arcane Blast's mana cost by 5% and increases its damage by 8%.

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  Arcane Tempo

  Haste increased by 2%.

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  Aether Attunement2 ranks

  Arcane Missiles now damages 2 additional targets at 50% effectiveness.

• 
  Aegwynn's Technique

  Casting Touch of the Magi grants Clearcasting.

• 
  Arcane Echo

  Direct damage you deal to enemies affected by Nether Flux, causes an explosion that deals Arcane damage to all nearby enemies. Deals reduced damage beyond 8 targets.

• 
  Resonance

  Arcane Barrage deals 8% increased damage per target it hits beyond the first.