How do I make a placed land mine set off a trigger?

I want to make a land mine set off a trigger as soon as it is created, and I want the mine itself to be the (triggering unit). However... for some reason there seems to be no "Unit - Unit is created" trigger, for reasons I can't fathom. Nor is there a "Player - Player creates unit" or "Player - Player controls unit" trigger, also for reasons I can't fathom. I can't figure out what to do...
Any suggestions?

Edit: Nevermind, I got "Unit enters area (entire map)" to work.