Set instance variable before creating it?

I'm just wondering how I can set the variable of a instance before it is created? I'm creating a bullet and I want to set its target destination before it runs its OnCreate script

Yes.

Just create the instance with the wanted number, text, etc, then, when creating the bullet, for example, set the bullet to meet the instance data.

scirra.com/tutorials/361/understanding-uid-iid-health-of-enemies-and-rocket-smoke-trail