Walls

How do you form good looking and tall walls (For example: here)

You uh, scale the doodads up large and stretch them.

In some parts, you can see doodads stretched, but look at the actual walls themselves. There isn't a doodad with that texture. It looks more like the actual tileset rather than an enhanced doodad.

Here's what I can notice.

The tall green rectangles are a custom model in UTM3, one of the sunken ruin pillars. Behind those are reinless's walls, which is what I believe you were looking for. He also used Blizzard Cliffs for the base of the walls.

Edit: The exact name is Ruins: Tall Wall (1)