Mining to destroy walls

[Mythos_Ruler]

I think there shouldn't be a maximum distance for tunneling. You're already paying for it (since its based on length like you said.)

There needs to be a way to counter it, so the distance must be relatively short.

[quantumstate]

There needs to be a way to counter it, so the distance must be relatively short.

The way to counter a long tunnel would be to scout around your base to detect the start point. I don't see why it i essential to be able to easily counter it as long as it takes a decent amount of time to construct and has sufficient cost. Many games have uncounterable weapons (e.g. nukes). Being able to knock down a wall in peace if the enemy isn't watching seems quite tame in comparison.

[oshron]

while, theoretically, you would be able to make a tunnel as long as you wanted it to be in real life, for the purposes of gameplay i think that it should be limited to a set distance with very high costs at greater distances. maybe it could be one in-game mile at most. the reason i think it should be limited is because, realistically, you wouldnt want your soldiers in an exceptionally long tunnel far away from any exit in case it collapses, which would become riskier and riskier the longer the tunnel is. for scenario design, though, special tunnels that can cross water and have indefinite range would be useful, much like the Underworld Passage in Age of Mythology

the tunnel collapsing, i'd think, would just overcomplicate things even IF its more realistic that way. just destroy the entrances and you'll entomb them before they can escape anyway.

another possibility arises, though, that you could use tunnels just to transport your units between your own territory, such as across otherwise impassable mountains or forest so that they don't have to walk all the way around.

as for sapping, i would personally suggest actual sapper units as a different siege weapon that civilizations that aren't known to use "traditional" siege engines could have. for exampe, for my mythology mod idea's Egyptians, i decided to give them some sappers as their one and only basic siege unit, functionally identical to a Ram even though they aren't ACTUALLY rams

[Asterixfan]

This may be too complicated, but how about counter mines? A player can counter a mine by building another mine to it and if he has more soldiers in his mine, the mine is destroyed, the counter mine is deleted, and the remaining soldiers exit through the mine's entrance.