the hero doesn't damage the target unit when it should
Then, when does he damage the target?
Additionally, that trigger leaks a lot. You leaked 2 effects, and 2 locations, I believe.
You have to create an array variable with value 2 and type Special Effect. Also create another point variable.
[TRIGGER=Do this]
Actions
Set Timestrikecastpos = (Position of (Casting Unit))
Set YourPointTypeVariable = (Position of (Target unit of ability being cast))
Special Effect - Create a special effect at (Position of (Target Unit of ability being cast)) using Abilities\Spells\NightElf\Blink\BlinkTarget.mdl
Set YourSpecialEffectVariable[1] = (Last Created Special Effect)
Unit - Move (Casting Unit) instantly to (Position of YourLocationVariable)
Unit - Cause (Casting Unit) to damage (Target unit of ability being cast), dealing 150.00 damage of attack type Spells and damage type Normal
Wait 1.00 seconds
Move (Casting Unit) instantly to Timestrikecastpos
Special Effect - Create a special effect at Timestrikecastpos using Abilities\Spells\NightElf\Blink\BlinkTarget.mdl
Set YourSpecialEffectVariable[2] = (Last Created Special Effect)
Custom script: call RemoveLocation(udg_Timestrikecastpos)
Custom script: call RemoveLocation(udg_YourPointTypeVariable)
Special Effect - Destroy YourSpecialEffectVariable[1]
Special Effect - Destroy Your SpecialEffectVariable[2]
[/TRIGGER]