Who thinks that it would be a good idea to add in stone, wood and cobble vertical half blocks these blocks are made by stacking three of each item of which you wanted the half block to be made out of. The blocks could then be used as walls, therefore you don't have to have very thick walls?
I personally think the 8th block idea is a pretty good one (in someone's sig or search it). Uses up none of the limited IDs and makes detailed work possible. It would also let you do exactly this.
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= a vertical stone block?
But be wary. I've seen this idea a number of times before.
Wraiths: Boss-like mob for Hard!