...you could try a couple of different things, to get the effect you're after.
1. Stack the seperate entities, and perhaps have the bottom one be destroyed by triggerzone activation, causing the upper entities to fall downward.
2. Assemble all the pieces in your 3D modeling program, rig them, animate the collapse, export it, and introduce it in
FPSC as a new animated entity.
Then, all you'd need to do is activate the collapsing building entity with a triggerzone, which will run the animation.
Of the two, the second one is the better choice. Once in place, you'd have a really good effect that you could use effortlessly, with just a couple mouseclicks.
Option #1 would probably be a hassle, cause all kinds of physics problems with collision issues, and you'd never be able to predict or control how everything will react.
Best of luck in your future endeavours.
Thanks,
Seth Black
EDIT: Shucks, Plystire beat me to it. The barrel idea sounds like it might work. I think you'll still have collision and physics woes, though.
Good to see that all involved believe animating the event is the best way to go.
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