A reason for a solid foundations for your building. Collapses.

[starXephir 30]

Well the floating castles would be most susceptible to being hit with the 'destablizing' charge. Which I would have figured shot up in a cone-like effect, not a giant chain reaction that kills the server. Then the non-air blocks and downards collapse (or chance based, for some cool looking rubble), starting from the bottom. So the skilled sapper would be able to aim for spots where foundations are weakest, or the construction is overly done. When the charge checks for non air blocks, it would have a max range... Placing it at the core of the world and firing it up into a city would just be rediculous, but would allow the sapper to choose an optimal depth when detonating for maximal damage.

 

Keeping the construction minimal, or using well spaced out supports would be the best defence against the charge. Many supports my be blasted loose, but the further out beams will keep the damage at a minimal. Saving them from building layers and layers of stone. Sappers may require a decent knowledge of the support structure before hand, or just blast it in the courtyard and enter that way haha.

 

Edit: The IC2 server thing sounds hilarious. On a full tech server you could making a fully self-sufficient shelter. Just don't forget a good supply of water chips.

[Kazahied 42]

Yea, my bunkers were lovely when i played IC2.

 

I think that the less secure a structure is the less resistant it is to sapping. I mean a 6 meter thick stone wall is basically impervious to direct blasting. I think there should be no loss of resources though, (the rubble idea is good) by having the materials fall into rubble blocks that are colored based on the dominant material in the pile you can save tons of id's. The rubble would act like gravel and pile like coal or snow. To clear the rubble players would need to use a shovel to dig up the materials. (for simplicity the rubble would only accept a single type of material per pile)

[AllenWL 186]

I'd like it if the 'collapsed blocks' turned into a gravity-effected counterpart, say planks into 'collapsed planks' and logs into 'fallen logs'

Upon breakage, they would drop their non-gravity-effected counterparts.

 

This could actually be helpful to defenders as well. say, a part of the wall blew up.

Normally there would be a gaping hole for enemies to pour through.

But what if, by sheer chance, the wall collapsed? it could make a wall of rubble, that while significantly weaker then the original wall, will still hamper the enemies trying to get in