a way to unoptanable placeable blocks here is an example (line 1).
line 2 is a moving piston that has interesting properties
and line 3 is a block you can go thru, also if you place 2 end portels you get an invisible end portal, (same with others)
also, line 4 + 5 is a blank template, if you want to make any block then (4th line is solid, 5th is go thru block)
notes: replace {your block} to whatever block you want, make it a real block by using /setblock ~ ~ ~ { you block } if it is a block there then ok to do
also, credit me by my work with "made by sample_text1" any q&a ask me in comments