[Fish]

Originally Posted by Molon Labe

I'm pretty sure triggers are objects that can be included in dynamic groups. You might be able to do what you want by creating a master group with several subordinate groups inside it, each of the subgroups having set to a certain probability of inclusion and containing a trigger set to fire at a specific time. The game would choose which groups--and triggers--to generate at the start of the mission.

Thanks ML, I was aware of that possibility, but Miika's solution is easyer to do.