New Super Mario Bros. 2

[Mutsukki]

Multiple breakable bridges is an idea.
Break the bridge, Bowser falls.
But wait! There is a bridge under a bridge! And for each bridge, the battle gets more challenging (harder-to-dodge fireballs, less platforms, longer bridges to cross)
...
Why am I pitching ideas?

Super Mario 3D Land last boss is kinda like this.