"on collision with" worked perfectly. Thanks again.
But here's another question...
Is there a glossary of some type that shows you all the possible functions for events and actions, and where to find them? Sometimes just reading all the options inspires an idea. I didn't notice the "on collision with" or "trigger once while true" functions before because I was fishing for ideas inside and existing event that already had a trigger active, so it didn't show all the other possible trigger events.
There are also functions that are only found under actions or events. It seems like a glossary would be handy, or maybe even have the functions greyed out with a help window explaining why they are not available.