Originally posted by rapier1955:

Not heard of directional terrain grids, please elaborate

The ground in Valheim is a height map. There's a big grid of X and Y coordinates and at each coordinate there is a height value. Basically think of a giant sheet of graph paper with height values written in each square and you'll have the right idea.

If you follow the grid your earthen wall will look straight. If you don't it will be jagged.

You can use stone walls to clad your earthen walls and it'll look better while still providing protection (although you may need to hit them with a hammer every so often)