Need help with blocks falling when disconnected

I am making a sidescrolling survival game, where you build shelter from materials around you, and i want to implement destrucion, like when a group of blocks are disconected and suspended above nothing, it activates physics, and they all fall.

Heres a great example

youtube.com/watch

My approach would be to use multiple behaviors on the blocks. Like the video, I would use physics in combination with pin behaviors. When a block is removed and the Y position of any block changes, pin can be disabled and physics can be enabled. It also depends on the specifics of your game.

My approach would be to use multiple behaviors on the blocks. Like the video, I would use physics in combination with pin behaviors. When a block is removed and the Y position of any block changes, pin can be disabled and physics can be enabled. It also depends on the specifics of your game.

I dont get when the y position changes. How would it change if physics isnt enabled