What size should textures be created in?

Does 128x128 look good ingame if you designed them in 1024x1024 etc?

Any golden resolution?

Just 512x512 works on everything.

You can try any but 512 is most used

512x512 is the most suitable resolution to work on as textures are automatically resized,
so you would be able to use those textures on any resolution texture items and if you
decide to upgrade to 512x512 later down the road, you'd know exactly what it'd look like.

Also, about them looking good on 128x128, that is really for you to decide..
Like people were telling you in your previous thread, what you think is "good" could be
different for everyone else.
Anyway, 128x128's aren't really made for detailed textures, pretty much just for simple
shapes and colors.

If you make a texture in 128x would look better than a 512x resized in 128x. But nearly every artist uses 512x if there isnt a specific request for other sizes.

Generally you should make them in the resolution you intend to display them in. Although you might find it difficult to display subpixel detail, it's less random than resizing and hoping it works out.

The general process is work in double width (ie 256x128) until you have most of it done, then resize to the size you want (128x128) and finish it off.

All right, thanks people!