This Requires You To Stack A Wall Up 30 High. (30 Wall Tiles Stacked)
But You Will Need To Build Another Wall, At Least 26 High, Right Next To It, To Support It.
- When The Villagers Build The Last Wall Tile, At Least 30 High, Achievement Should Pop.
- Go Ahead And Put A Ballista On The Top, It Will Have Insane Range.
- One Set Of Castle Stairs At The Bottem Will Make Any Sized Wall Climb-On-Able.
Good Luck!