Lava Cloud Effect - Page 2

Step 1
Create a movie clip and call it Blobs. Don't add anything to it yet, we'll do this later. This will form the basis of you lava cloud effect. Now drag an instance onto the main timeline and call it B1.

Step 2
Set the visible property of that instance to 0 by selecting the movie instance and choosing Modify > Instance. Next select the 'Colour Effects' Tab and modify the Alpha to equal 0%. (we don't need to see the parent movie clip we are going to create copies at different levels of Alpha visabilities)

Step 3 (Here's the clever bit though it's very simple)
Add the following actions to the 1st frame of the main timeline

Set Variable: "i" = 0
Loop While (i <%lt%> 4) 
    Set Variable: "i" = i+1 Duplicate Movie Clip ("/B1", "B"&i, i)
    Set Property ("/B"&i, Alpha) = 10+(2*/:i)
    Begin Tell Target ("/B"&i)
        Go to and Play (/:i*2)
    End Tell Target
End Loop
Stop