The_blood, you should be
freaking specific...
I bet your "Storm Hammer" is based from DotA Hero, Sven The Rogue Knight, is it ?
And the name is "Storm Bolt", not "Storm Hammer".
You should have been more clear and specific on this matter, not all play your game (DotA), luckily I do and understand what you're trying to request, next time be specific.
@Lysho
If you played DotA before, you should know Storm Bolt, the spell itself is based on Storm Bolt from the default spell by Blizzard, BUT, the only difference is that it supports AOE stun when the bolt reaches to the target.
So you cannot just;
So copy a different spell like the neutral hero ability Cluster Rockets, but change the model to look like a storm hammer.
The spell only throws one hammer and indeed a "homing storm bolt".
If you base it from Cluster Rockets, it's not homing at all.
Therefore, you
must trigger it by making dummy move to the target and kill the hammer to remove dummy and stun nearby enemy unit + deal damage.