How do I add collision for specific families?

Right now I'm using the Solid behaviour on my player character and enemies to prevent them from moving through each other. They are in separate families for obvious reasons.

Now I want to add a "friendly NPC" family that will attack enemies but allow me to pass through, so the Solid behaviour on its own wouldn't be enough to solve this.

Is there a way to do this with the Solid behaviour or do I need some fancy events?

Is this a platformer game? Using Solid behavior with moving player and enemies is not a good idea. I would probably do this with events instead, using "is overlapping" and "is overlapping at offset" conditions.

Fixed this by using the "On collision with another object" condition and the "Stop" action on the 8 direction behaviour.

This didn't work with the overlap condition since the player would just gradually move through the object anyway. I don't really know why that happens, but it works now.

Never mind, I only just now realised I had left the Solid behaviour on... any other input is appreciated.

Here's my project file: ufile.io/pzdib

Right now it's just two objects with the 8 direction behaviour, and that's it. In the future I want the enemy to chase the player and start attacking on collision.

I've tried your example, but the objects will just push each other around. I've also tried using Set X instead of Simulate Control, which causes a lot of jittering.

I don't understand, so you are controlling both the player and the enemy?? Or is this a temporary thing, just for testing?

Try this one:

dropbox.com/s/18yv1gkey4zsm6e/projectscroller.c3p