3D model volcano with effects (UNITY)

I want a 3d model volcano that looks like this [login to view URL] with 2 buttons First button will split the volcano into a half just like the video and an interactive activity will start .. it will be dragging and dropping 3 rocks into the volcano. After dropping the 3 rocks into the volcano .. the 2nd button when pressed will turn this rocks into lava and then the volcano will go back as a whole with lava coming down & smoke