okay, so i was playing laser intro stairs (main portal2 lvl)
and i saw 4 panels smasing against a wall and had two sounds to it and changed skin.
i'm wonder.. how do you do that?.

Use a more descriptive title next time, and this post is in the wrong section. As for the panels changing skins and smashing the walls, just make it play an animation and change the skin using the "skin"output.

srry what section is it? ill delete it if i find out..... and is there a way to do the two different sounds too?

Hammmer and Modding.

Also, the sounds will automatically play when you set up the animation. My advice is decompile the map, open it in Hammer, then copy/paste the entire thing to your map.

Instanced for your pleasure:

error_wallarm_4way.vmf

Start with trigger or logic_auto.

thx!