Random number sequence?

Here is a quick way to do this. 

1. Add your first image to the page. 
2. Add various states to it (I did 1 to 10). 
3. For each state, edit the image to a different picture (for consistency you might want them to be all the same size/aspect ratio). 
4. Then create a random number variable. 
5. Create a trigger that changes that variable when the slide starts.
6. Create another set of triggers that change the state of the initial image to one of the states you have created if/when it equals random number X.
   
   See attached file.
   
   This is just one possible solution to this idea.