How to set the alpha of lots of GO's at same time?

Ive got lots of GO’s (small tiles for a mini map) being attached to a parent GO. How can I make all of the mini map tiles be slightly transparent? do I have set the alpha of each and every one? or can I just change the parent GO and it will effect all the children?

If you’re talking about UI game objects, add a Canvas Group component on the parent. That component has an “alpha” property that affects all the children.

If you’re talking about objects that are not part of the UI you have to iterate over all of them.