(I am talking about free multiplayer server.)

Ok so I have had a look around the forum and it seems to be that there is nothing to allow me to build /solid blocks that aren't just the normal default solid block in the game.

The topics I came across where a tad old and I have gone on a few servers that do actually have coloured blocks that you can't destroy. If there is something that you can stretch over a certain part of the map or even just make it so more of the blocks can be used as solid. (Links to the program/mod/script would be great!)

Thanks in advance for any help!