NPC Invader Raids

We have expanded the NPC Invaders system. Now, when the threat counter in a room runs out, there is a 10% chance that you will get not only a lone Invader but a whole company of them, from 2 to 5. Each Invader has its own role: melee attacker, ranged attacker, or healer. Ranged attackers are different from melee ones in their behavior: they try to stay at a distance from your creeps. The function of healers is evidently to heal other raid members. Also, some creeps may be boosted with , , , or . Sometimes the total healing effectiveness of such a raid will surpass the damage from several towers, so defense will prove to be very interesting.

These creeps will stop using rangedMassAttack, so in the majority of cases they won’t pose any threat to your buildings except ramparts and walls. The worst result for you would be the death of all your creeps in a room. Certainly, you should try to avoid this to keep your economy stable.

  RCL < 4 RCL ≥ 4


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  • Amadox

    Honestly, this sounds a bit excessive/harsh, especially for new players. RCL 4 is reached very fast, and I don't think I would've been ready to deal with that when first reaching RCL 4. I'm not sure I'm ready even now in my RCL 6 rooms.

    The game is hard enough for new players as it is (thanks to other players), doesn't need NPCs to artifically make it worse. 

    If you want players to do more PvE stuff, maybe think about making the Invader rooms more attractive instead of forcing them on us. All this does is making players focus even more on walling themselves in and defending, instead of going on the offensive.

    Edited by Amadox
  • Avatar
    Artem from Screeps

    Defense is very important part of this game. It should involve not only simple logic like "find an enemy in the room and attack it with towers", but more complex scenarios as well.

    As we mentioned in the previous post, there is a 1M energy threat delay for new players when they first spawn in the room, it is quite enough to build solid defense.

    > If you want players to do more PvE stuff, maybe think about making the Invader rooms more attractive instead of forcing them on us.

    If you mean Source Keepers, they are very weak and can be handled on constant basis with simple algorithms. Invader raids are intended to bring some dynamics and unexpectedness in the game.

  • chris

    I think, this change would further increase the gap between top-level players and weaker players. The scaling is completely unreasonable. I just encountered a fully boosted healer in one of my new rooms (lvl4, but still weakly defended) and there is nothing I can do (locally) to defeat the invader pack.

    The scaling should depend not only more fine-grained on the RCL but also on the GCL of players. A top level player is far more likely (or at least should be) to defend their 100+mio rampart 4 tower RCL8 rooms against 5 boosted creeps, than sombody with GCL1 who just hit RCL 4.

    Imo the scaling should be something like this:

    RCL1-3 1-2 creeps, 10 bodyparts

    RCL 4-5 1-3 creeps, 30 bodyparts

    RCL 6,7 1-4 creeps, 50 bodyparts

    RCL 8 2-5 creeps, 50 bodyparts

    RCL8 + GCL > 10 boosted

    RCL8 + GCL > 15 boosted with OH

    RCL8 + GCL > 20 boosted with X

    Also I think you are steering the game in the wrong direction. Rather than introducing random PvE, you should think of means to encourage and reward PvP...

    There are a lot of ways to do so (like myself and others already suggested in the forum a long time ago, but you seem to barely pay attention to the forum anyway:-( ), e.G.:

    1) Introduce an "Expansion" or "War" ranking, counting destroyed (player) creeps/buildings.

    2) defeated creeps/buildings could drop Mineral(compounds) or directly contribute power points to the account.

    3) Conquering could count towards GCL points

    Bottom line...

    There are so many options to make the screeps world more interesting, but you choose to take a PvE element, which discourages, and most likely even decreases player to player interaction, because everyone is busy defending themselves.

    Edited by chris
  • Avatar
    Artem from Screeps

    @chris There is an internal mechanism which decides what the raid will look like depending on the room parameters. We won't publish these inner formulas since we don't want it to be a part of players' code.

    One (even fully boosted) healer is not a problem for RCL4 when you deal with it properly, spawn some defenders and don't fully rely on your towers. Or just ignore them and repair the damage. Challenges are funny part of any game.

    As to all PvP suggestions you mentioned - they bring huge abusable factor which allows two random players to boost each other's rankings easily. Such player-dependent rankings are not considered a robust game design generally.

  • chris

    MMO player to player interaction is always prone to abuse, which however is no reason to abandon these elements. They are core to good MMO, so you have to think about means to mitigate the problems (and yes, I know that it's a hard task, but I wasn't denying that in the first place) instead of discarding the whole concept.


    Edited by chris
  • Hernanduer

    It seems like just avoiding the room until the invaders die is a cheaper option than having to fight them off (with regards to non-owned rooms.)


    There should definitely be some sort of bonus to actually killing a raid, and not something like dropped energy that just reduces the efficiency of the mines that already exist since the carriers would have to be diverted.

    Something like +1000 ticks to the controller's reserve timer or something, though of course that wouldn't work for middle rooms. It needs to offer a reason to spend several thousand energy to fight off the invaders (not to mention any creeps spawned for the sole purpose of this one raid will be useless afterwards.)

  • Anton from Screeps

    @chris The question here is not just about interaction, but the ranking system where players themselves set the rules. If we want the competition to be honest, the game should control the environment in which this competition takes place. If, however, the environment can be controlled by players themselves (for example, by staging automatic “rigged matches”), the competition becomes senseless. All the MMOs I know adhere to this principle.

    We plan to implement the PvP ranking later, after the deployment of power creeps. It will be based on arenas separate from the main world, and each player will have not more than one power creep. But in the main world, such methods will result in manipulating points and nothing else.

    @Hernanduer Yes, this tactic is possible, it depends on you. The main thing encouraged by this update is to write code that is able to properly assess a threat and adapt to it rather than just repeat the same algorithm over and over again. After the emergence of power creeps there will be even more tactics for fighting raids.

  • Dissi

    Personally, I like the general idea behind this update, it gives players an idea on how to fend off enemy creeps.

    The way it's now implemented is not a good idea. I think that about 80% of the current players have 0 to nothing to defend against this, and implementing it will require quite a bit of time. If you pair this with the RCL level, a lot of players will die the coming weeks and will probably quit because of it.


    The other concerns I have are, as Hernanduer said, there is no incentive to actually kill off the invaders. It's more of another nuisance to deal with for "top-tier" players, but for smaller players it could be a killing blow.


    I think you should really reconsider some form of rewards system for killing off these squads before pushing the update to the production server.


    There has also been heavy discussions on the IRC channel, if you want I can send the chat logs related to this in a support ticket.

  • Avatar
    Artem from Screeps

    @Dissi What do you mean by killing blow? Invaders do not touch your structures. If you can't protect your colony, they will just kill off your creeps in the room and disappear. It is not something that could break your game entirely.

  • Dissi


    Killing blow as in, they'd stop playing. It was more a figure of speech.

  • Amadox

    Yea, I agree to Dissi. Loosing all your creeps in a room for about 1500 ticks might not seem a big deal to you, but to a new player, having  that is quite a blow, and being confronted with multiple 50-slot-creeps that wreck your walls/ramparts, leaving your base wide open, and keep you from spawning new creeps entirely (because you can't possibly spawn a single creep that could challenge them) can easily be perceived as "unfair", maybe even as "punishment", even if they are gone again after 1500 ticks. 

    You seem to severely underestimate the challenge this game presents to new players as it is. 

  • Avatar
    Artem from Screeps

    @Dissi Yes, so what did you mean by that? Why would they stop playing because of that? Why would one stop playing Starcraft when he fails his first mission?

    @Amadox A player might not even notice that if he was offline and has a proper auto-spawning code (which is Section 4 in our new Tutorial now).

    Also, invaders will go away not in 1500 ticks, but suicide immediately if the room is owned and all your creeps are defeated.

  • lahilahi12

    Are you kidding me? I'm totally cornered in some room and have nowhere to spread, and now these are just gonna come in and disturb me. aww. welp, hope my 4 layers of walls will keep these raiders off until they die. Can healers heal themselves? Because I have advanced code on my towers that prioritizes screeps with heal body parts. I hope that comes in handy.

  • Amadox

    yes, creep.heal(creep) to heal the themselves works.

  • ciaosu

    This is absolutely ridiculous. The first time this occurs for me, an attacker and 2 healers show up. I'm RCL5 and just hit GCL2, but there is nothing I can do against 50 part creeps with 2 healers. With only 1 attacker they were unable to get through my walls, but did manage to knock off about 400k health from one section of wall. I could have dealt with 5 attackers more easily than these healers. I had to just sit and watch them for 1500 ticks..

    In any other MMO, players aren't dropped into what amounts to an end-game dungeon and forced to try to solo the content. If another player was attacking me, I would understand that they could be a lot more advanced than I am, but having the PvE content scale so unfairly doesn't make any sense. Players shouldn't be forced into PvE content in which they have no chance of winning, they should be able to make that mistake voluntarily.

    To Dissi's point.. I'm not going to stop playing solely because of this since I already bought the game, but why would I want to renew my CPU subscription when my first month ends? What other unpleasant surprises are waiting that I don't know about yet?

  • Avatar
    Artem from Screeps

    I’m RCL5 and just hit GCL2, but there is nothing I can do against 50 part creeps with 2 healers.

    At RCL5 you have 2 towers, that is 1200 damage per tick at close range. 2 non-boosted healers (you can't get boosted invaders at RCL5) heal only for 600 hits per tick. All you have to do is to program proper non-stop filling of your towers, and probably move them a bit closer to the room edges to optimize their damage.

    I had to just sit and watch them for 1500 ticks.. <…> I’m not going to stop playing solely because of this since I already bought the game, but why would I want to renew my CPU subscription when my first month ends? What other unpleasant surprises are waiting that I don’t know about yet?

    Yes, if you can’t handle the invasion yet, the worst thing you have to endure is to wait for 1500 ticks until they are gone, as they do not attack your structures and neither do they any other permanent damage to your colony. Is waiting for ~1 hour really that unpleasant for you to think about quitting?

    Edited by Artem from Screeps
  • ciaosu

    I understand that you, as a creator of this game, have substantial knowledge of this game. I will also freely admit that you are a better developer than me. The reason I purchased this game was that I figured that not only was it going to be fun, but that I could improve my coding skills at the same time.

    However, as a player with under 20 days of play time, I'm saying you are giving me zero reason to support your game. I average 2-4 cpu usage per tick and the subscription has no real benefit at this time. I was planning to support your game regardless because I believe it in, but if I don't feel that way why should I bother?

    At my current level, I have 1800 room energy maximum am using up to 900 on a single creep. I haven't had the time to worry about figuring how to dynamically adjust the creep body parts based on what energy I have available. If I start dumping all my energy into the towers and then creeps fail to spawn, I'm at way more of a disadvantage.

    I have two towers to defend 4 areas of my base that I built walls around. Chances are I'm not going to be doing full damage no matter where I place my towers. I'm not saying that the setback was so substantial that I can't recover from it, but the psychological effect on my satisfaction with the game took a large blow. I was prepared for another player to come at me, but not this garbage example of PvE content.

    Now, I am saying that if you are incapable of relating to players who are new to your game and not already proficient developers, you better be content with the small player base you have. If that's what you are looking for, then more power to you.

  • Avatar
    Artem from Screeps

    You have stated that it is ridiculous and impossible to do anything against 2-healer invasion on RCL5. I just pointed out that it is possible in fact, and even not really difficult (you don’t need maximum damage from towers, maximum is 1200, you need only 600).

    It’s just another challenge in this game. Challenges are fun! And NPC invasions are not even the most challenging aspect in Screeps, since they don’t hurt you permanently. Just keep trying, it will be satisfactory when you manage to handle them properly eventually.

    I was prepared for another player to come at me, but not this garbage example of PvE content.

    Actually, a player invasion will be a lot more difficult to stand against than these simple NPC raids with a few creeps and basic logic. It is the purpose of this mechanic, to help new players build and test their defense properly in relatively safe conditions.

    Edited by Artem from Screeps
  • Amadox

    This is what I was trying to say back then, and you still don't seem to understand:

    Ofc player attacks could be way harder. But thats okay, because that player worked hard for that, to get there, to be that threat. When he says he's prepared for that, I'm guessing he meant that he's mentally prepared to be beaten by someone better.

    The PvE creeps however didn't work to be better. They just are. And it doesn't matter how easy -you- think they are; for a new player they are tough, and extremely discouraging. You don't see the big issue with waiting 1500 ticks, but the players do: It is defeat. It -feels like- defeat. This PvE thing just randomly comes in, wrecks their walls and creeps, and in that moment there is nothing at all they can do. At least it feels like it. Sure, mathematically they might have been able to beat it, but the world isn't just math and coding, not even in screeps.

    These invaders just are not fun, they are somewhere between frustrating and a nuisance depending on your progress. Even the biggest players mostly just "sit them out" as far as I have seen. I have talked to a bunch of players and nobody likes them. Not everyone has a huge issue with them, sure; but nobody ever went "yey, invaders!"

    Whats the point in having a mechanic that everyone hates, and that adds *nothing* to gameplay? To "prepare you against attacks"? Nobody needed that. We learn from attacking other players and defending against their attacks. Thats how it should be. We don't need or want invaders.

    It was an idea that sounds interesting on paper, but in game just isn't. It's annoying and thats all it is.

  • Avatar
    Artem from Screeps

    We do understand your point, and it is much appreciated that you express your thoughts here. However, you don't see the whole picture, as we do. We implemented this mechanic based on many hours spent watching new and old players rooms history, and we see positive trend in how new players build their defenses now thanks to the training by the NPC invaders system. They force you to think about your defense constantly, starting from your early game. It is not possible to achieve with player invasions only, since player invasions are well planned and most likely are always successful, you will not get a chance to test your defenses again and again in the same setup, you just lose and respawn. Hence, there is much more grief without NPC training system than with it.

    This is our deliberate position, we're confident in it. We see many proofs, it's not just theory. Again, we appreciate your feedback, but I'm not going to argue on this point anymore.

    Edited by Artem from Screeps
  • Amadox

    Fair enough. Then maybe think about finetuning it, giving it more of a curve, starting with smaller creeps, making sure healers start appearing later, and reducing the randomness in strength at least early on. At the moment it just starts rather harsh and sudden for inexperienced players. Start with really tiny ones. 1 attack, 1 move. Let them grow over time. Keep a hidden score for the player maybe that increases when the player manages to beat them without them just dying of old age, and decreases when they fail, and use that to scale the next wave. Or even better, make it a visible score players can boast with. Turn frustrations into motivation.

  • Avatar
    Artem from Screeps

    Sure, we'll keep watching and tuning almost every game aspect to make the balance better. There are more important TODOs right now though.

  • Zortea

    I like the idea of invaders, but I wish they were more balanced, more frequent and less strong. 

    The thing is, its hard to test your code regarding invasions. You Artem with countless hours watching the game and full knowledge of the game rules probably knows exactly how its going to happen, but me as a new player, I have no idea how an invasion is. I make a code imagining one way, and something completely different happened and there was no way I could have been prepared for it, worst, it can happen while I'm at work and I know my colony is being destroyed but there is nothing I could do about it.

    More frequent invasions would allow players to actually test their code while they are watching it happen, they would be more prepared for it and it would be fun. Hell I wish I could intentionally trigger an invasion so I could see what happens and try out new strategies. 



  • RyanYesThatRyan

    I was lucky enough to be watching while my first round of invaders came in. Couldn't do much, but I learned how they behaved (and how strong they were!)

    I tried building some automated defenses, but I can't test them. It seems the simulation doesn't let you build NPC invaders - the item is there but clicking anywhere with the "NPC Invaders" item selected doesn't actually create an invader.

    How are you guys testing your invader defenses?

  • Avatar
    Artem from Screeps

    Use "Invasion" controls in the room side panel.

  • bkfarns

    For what it's worth, I'm a relatively new player (started really playing basically in Nov 2016), and I don't find the invaders very difficult.  All you have to do is make sure you can attack with more attack points per tick than the invaders can heal.  And like Artem said, that's pretty easy with two towers. Especially if you can get the towers built in close range to the entrance, then you get the close range attack of 600 hits.

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