We could have...
Domino walls, domino pillars, cones moving all over the place, rolling spheres, fragmenting balconies, falling objects... --Breath--
Yes there is a lot that we could have. But let me simplify. Here we learn how to make objects that fall on you or must be pushed over. So let's start.
Objects To PushEdit
How do you make an object to push? By creating the model for a start. Make it and then put it in the position you would want it to be in. Set it as Dynamic in the physics. Now play and push it over. Should work.