You always need an action to control, testing
entity movement, collision. To detect an entity
hit by another objects without event_entity,
event_impact or whatever, you may try trace_hit :

Code:

---

action snowMan
{
   while(my != NULL)
   {
       c_move(...);  // it's a must
       if (trace_hit)
       {
           wait(1);
           ent_remove(my);
       }
       wait(1);
    }
}

---

By the way, you have to add some "ignore_" options in c_move
if the snowman is on the ground for example.

Hope this help!