Ability to permanently remove a non-constructed wall tile from a room (for an extremely high price)



  • would it be possible to make it cost 100-500 ghodium to build? No idea what the maintenance should be



  • @artch What if we allow building roads on walls,

    Why would we do this when we can build ramparts with roads on them for the same price as a wall & road with slightly higher maintenance.

    Or are you suggesting sappers ie building tunnels in hostile bases.


  • YP

    I like the idea of tunnels 🙂

    but I guess they should be only allowed in own rooms ?


  • Dev Team

    @stevetrov I mean roads in natural terrain walls.


  • Dev Team

    @w4rl0ck

    but I guess they should be only allowed in own rooms ?

    Not neccessarily. It might open some interesting tactics in neutral rooms too.


  • AYCE

    Could be neat to tie UO boosts into the ability, whether it be to boost tunneling speed or as a maintenance cost. Seems related (in my mind) and might add usefulness to what appears to be an under-utilized boost.



  • @artch said in Ability to permanently remove a non-constructed wall tile from a room (for an extremely high price):

    What cost ratio seems reasonable for tunnels?

    If we're talking energy only I would go for 25x the cost of swamp roads (or 125x normal roads): 12500 hits every 1000 ticks. That works out at 12.5 hits/tick, or 0.125 energy/tick. That puts the cost to build at 37500 energy, and hit points at 625000 which... seems a lot. Maybe the hits could be toned down, but the energy cost seems alright.

    My justification is this: I don't want tunnels to be a no-brainer. Nor do I want them to be a one-off cost (as that quickly gets amortised over time). There are plenty of situations where paying 0.125 (or 0.25, or 0.375) energy per tick is worth it compared to going around.

    For example: a RCL 7+ hauler costs 2500 energy. If I can reduce its average trip length by 10% with one tunnel I "save" 250 energy, or 0.17 energy/tick, so there's a net profit. The number of places you'll be able to save that amount of time are probably fairly infrequent, but they exist.

    I had originally thought 50x and I think maybe that's too high. Not sure.


  • SUN

    @tigga Considering that 'tunnels' literally alter the 'shape' of the room having hits that high means that it is possible to meaningfully defend critical tunnels without ramparts.

    I feel that the costs are if nothing else, a good starting point too. A major point to note with the costs is that a single tunnel is very rarely going to be enough to bypass obstacles; Two at minimum seems to be what is required in the vast majority of use cases.



  • @artch, I like the tunnels idea! Some thoughts:

    • Should it be allowed to build tunnels at rooms edges? I guess it's very tricky to implement and make compatible with current path finding.

    • Not neccessarily. It might open some interesting tactics in neutral rooms too.

      ...and not only neutral, but even enemy rooms! As a neutral structure like roads (with neutral construction sites?) tunnels can make possible some powerful "backdoor" siege tactics.

    Still, I guess, tunnels will become very high-level and late-game feature and for high-level players only, so it's questionable is it worth to implement. Well, but as a community contribution and for some tokens (like awesome super fancy Tombstones) -- why not? 🤔



  • @mototroller A lot of the old guard left due to a lack of new features. Depending on how well this was implemented, it might be enough to bring some of em back... Do not underestimate "late game features." 😛



  • @mototroller I like the idea of being able to build in hostile rooms- it wouldn't necessarily be easy, or even useful most of the time, but simply having the option is significant.

    Overall, I like the idea.



  • Late game features are what this game needs more of. There are lots of early and mid game features. Whether this is actually a late game feature I'm not sure: it's basically a road with (hopefully) a more complex cost:benefit decision to be made than roads as they stand.

    There's quite a few additional complications if you allow construction in hostile rooms. I think you'd want the construction site to be attackable, for example. There's other backend changes required such as allowing construction sites in hostile rooms. In general it feels a bit too much like a special case.

    While being able to tunnel across room boundaries would also be interesting, I think I'd be against that as well. Too powerful/game changing.



  • For the simple case of just building road over the top of terrain walls, I like think a x25 seems reasonable(swamp is 5x more than plain and wall is 5x more than swamp). If that's not enough maybe a 50x bump, but Tigga's suggestion of 125x seems a bit too high.

    Being able to travel over walls doesn't seem to be too powerful. Honestly, I might even go so far as suggest that we allow any structure to be built on a wall. This might also create some new base layouts with extensions packed into the walls, or spawns heavily defended with terrain walls on 7 sides. It might also make for boring bases since the natural terrain is no longer a hard constraint.



  • @deft-code said in Ability to permanently remove a non-constructed wall tile from a room (for an extremely high price):

    For the simple case of just building road over the top of terrain walls, I like think a x25 seems reasonable(swamp is 5x more than plain and wall is 5x more than swamp). If that's not enough maybe a 50x bump, but Tigga's suggestion of 125x seems a bit too high.

    I had forgotten about creeps stepping on roads in my calcualtions, so maybe I was a bit high. IMO 0.025 energy/tick + 1.25 energy every time a 50 part creep steps on you is too low though. Maybe double that (eg. 50x) would be ok.



  • The idea of Sappers who build a path through a wall as another way of breaking bases is pretty interesting. You could use energy from dismantling on one section to let you sap another section.



  • Tunnels with a relatively high maintenance cost is a better idea than my original suggestion, I like it.

    Tunnels in neutral rooms would open up some interesting military tactics as well as economics...



  • Allowing players to build structures in hostile rooms is a topic we should pursue. I'm not sure whether it's a good idea or not. Just being able to build walls while attacking a room would a be a huge change. However, I think we've found a nice little feature with wall roads (I think the name "tunnel roads" is confusing).

    1. Allow road construction sites to be placed over walls.
    2. Increase the build/upkeep costs of wall roads 25 or 50.
    3. Update the engine to allow movement onto wall roads.


  • @tigga said in Ability to permanently remove a non-constructed wall tile from a room (for an extremely high price):

    That puts the cost to build at 37500 energy, and hit points at 625000 which... seems a lot. Maybe the hits could be toned down, but the energy cost seems alright.

    Regarding the idea of 25x swamp build costs, I agree that 37500 energy is almost nothing. You eventually have lots of energy in most rooms and in the lifetime of a room you will get through hundreds of millions of energy. So amortised over the room lifetime, 37,500, or even 375,000 energy is basically nothing. It will be paid if necessary (and if there was a mineral cost that would also be happily paid).

    The maintenance cost of 0.125 energy/tick on the other hand is definitely something to think carefully about. Let's say a room + remotes has a net energy income of 20-60/tick, if you dropped a few tunnels that could be a substantial fraction of the room's income. This would be the most important statistic of the tunnels to get right. Too low and the tunnels will be used very freely, too high and they would be used very rarely. Neither extreme would make an interesting decision for players.

    As to the hits of the tunnel, I actually think that the hit points of most room structures are negligible once boosts come into play, extensions can be 1-shot by a boosted creep, so I don't think the game would be worse if structures started being a bit harder to kill. Especially if there was a sizeable up front cost to building tunnels, you would want a bit of HP for any marauders to chew through to give you some chance to preserve your investment. Tunnels in neutral rooms would admit a new form of guerrilla warfare where you could cause economic damage to someone with hit-and-run attacks.

    Because the maintenance cost is the most important balancing parameter of a tunnel, lets have a look at a few rooms on the map I've found by clicking around and look at the consequences of some tunnels being built:

    https://screeps.com/a/#!/room/shard2/E5S6 - this is an SK room with some big walls such that if you were harvesting it from the south or west you'd have some really long paths. Imagine someone's harvesting it from the south, an obvious place to put a tunnel would be through the 3 wall tiles at y=40, x=20-22. This would cut short the path of an energy hauler travelling via the bottom right exit by 50 steps. If we assume a 33W17M hauler costing 1250 energy, in a creep lifetime that source requires 12+ visits (4000 * 5/1650). So 12 visits that travel 50 steps is 600 ticks of hauler lifetime that you save, or 500 energy (600/1500 * 1250). So if the tunnels cost less than 1/9 energy per tick (500/1500/3) then you make an energy profit from building them. However, you also make an intent saving and a spawn capacity saving. You probably also would make some intent saving on your source keeper killer creeps which wouldn't have to travel as much between source keepers.. So I would argue that those tunnels would still often be worth building even if the energy cost was higher than 1/9 per tick. A question for the audience: what would you pay, in energy per tick, to save ~half a hauler and spend the cpu/spawn capacity on a different creep?

    https://screeps.com/a/#!/room/shard2/W4S8 - this is a non-SK room. Again assume we're harvesting the room remotely from the south. The tunnels of choice would probably be 3 spots at y=45, x=19-21. In this case the path saving is about 40 spaces. Doing the same calculation again we find that we require 9 visits and save 360 ticks of hauler lifetime. In this case we make an energy profit if the tunnels cost less than 1/15 energy per tick.

    Clearly, in two somewhat similar rooms, each with 3 tunnels required to improve a path, differing mainly by the presence of source-keepers, we see that it's much easier to justify building tunnels in the sourcekeeper room. But in rooms with thicker walls it might be very hard to justify building tunnels.

    The important question is I think, what energy loss would you be prepared to take (if you would take any at all) to reduce the number of haulers you needed and gain more spawn capacity and spend less cpu each tick?


  • YP

    likewise with containers the upkeep cost could be different for owned rooms and unowned rooms.

    should it be possible to build tunnels through build walls ?

    should it be possible to rampart walls to prevent tunneling?


  • Dev Team

    Tunnels implementation have been deployed to the PTR: https://screeps.com/forum/topic/2322