Dev BlogsNull Sec Sov Fights

Citadels, sieges and you v2


Welcome back to another blog on structures by Team Game of Drones. You may be surprised that we are going to discuss structure protection and attack yet again, a point already tackled in Citadels, Sieges and You. This is mostly due to our quite radical change in direction regarding what we would like to achieve regarding structure assault mechanics – a shift that happened after reading feedback from various sources and extensively debating that point with the CSM.

Entosis links are not going to work on new structures

Long story short, we have had long meetings about the structure attack system, and came to the conclusion that, while Entosis Links do indeed achieve our design goals for the Citadels, they are not actually delivering an experience we are satisfied to provide.

  • It’s not fun being shot by massive structure weapons while being unable to retaliate in kind, it gives players the feeling to be helpless while they watch a timer go down
  • There is gameplay involved in applying damage that Entosis Links do not preserve, like range, speed, falloff or positioning
  • It devalues capital ships as a whole, especially Dreadnoughts, which were specifically introduced to assault and destroy static structures
  • Last but not least, there is a visceral connection in shooting a structure down to destroy it. Having guns blazing while watching the target hit points go down is a very strong visual and adrenaline factor that Entosis Links remove out of the equation.

So, there are several points that come out of this:

  • We are going to make sure we have mechanics in place to prevent problems with the existing Starbases – specifically that HP damage always benefits whoever brings the most ships in the field, since damage always scales by number. That is why incoming damage will be mitigated past a certain point (more on this below).
  • This will not affect the current Aegis Sovereignty system. We have plans to merge those systems when we move Sovereignty into the new structures and we will account for the specific needs of the Aegis Sovereignty system when that happens
  • We are aware Capital Ship are in the pipelines to be rebalanced, and bringing HP damage back into structures is not a coincidence. We want both structures and capitals to have a strong tie with each other, a binding theme delivers a unified and enriching experience. As such, the Capital Ship rebalance will definitely account for this HP damage system for structures
  • Wormhole space presents unique gameplay we want to preserve whenever possible. As such, variations will be made in the attack system for this specific area when we feel they are justified
  • All of the numbers, timers in this blog are still up to discussion and debate. If anything, we do believe we have proven so far that we were willing to listen to feedback and change our designs accordingly, so please make sure to remember those are not final numbers yet

Meet the new structure attack process

With that in mind let’s have a look on how the new attack process is going to look like.

We wanted to simplify it as much as possible next to the previous version. You will notice we merged the online and reinforced states altogether, which technically work the same way (the structure cannot be shot) – we also introduced the concept of a repair timer. More on that later.

We also removed the concept of three vulnerability and reinforced states. Since structures can now be damaged through regular means, we are simply going to represent that by using structure shields, armor and hull, which is a much more visual and familiar way to represent structure attack phases.

Vulnerable state

A structure enters this state during the weekly vulnerability window or after it has been anchored / unanchored. Damage can be applied to the structure in this state. When any kind of damage is received, the structure enters a repair state.

The weekly vulnerability window design hasn’t changed much from the last blog. This still represents a specific amount of hours that have to be assigned on a weekly basis, during which the structure will be vulnerable. Hours are assigned on a calendar and players with proper roles have control when they should happen. What has changed however, is that the vulnerability window will not vary based on Sovereignty indexes anymore, as this we realized it would cause management nightmares when trying to apply vulnerability hours while Sovereignty indexes are changing. Sovereignty indexes will instead modify repair timers (see below).

Citadel weekly vulnerability window M L XL
All areas of space 3 hours 6 hours 21 hours

Example from the last blog in case people missed it:

Soft Croissant Incorporated™ is a small 5 man corporation having a Large Citadel structure in high security space with 6 hours of weekly vulnerability window. Not being a hardcore gamer, the structure owner decides to set the vulnerability window 2 hours during Tuesday evening and 4 hours on Saturday. During that time the structure will be vulnerable to damage (a war declaration is still needed to shoot a structure in high-security space).

Invulnerable state

The structure cannot be attacked through any means when in this state. It serves to protect the owner assets, pauses gameplay and gives a chance for all players within different time zones to interact with each other.

  • It is the most common structure state, encountered when a structure is operating normally, being anchored or unanchored, or after a successful attack by external parties
  • Unlike existing Starbases, the new structures will not use fuel when invulnerable. In fact they will not use fuel at all by themselves. Fuel consumption has been moved to service modules, which will use a new type of fuel blocks, made of the materials from all existing fuel blocks, plus strontium clathrates. This will be explained further on a separate blog on Structure acquisition and composition materials

Invulnerable state duration:

  • Shields will be invulnerable all the time, except if the structure is within one of the weekly vulnerability window mentioned above
  • When vulnerable and attacked, if shields hit points reach 0, the structure will become invulnerable for a specific amount of time (this is the equivalent of the old reinforcement timer). Exactly how this is going to last is still up for debate. We are discussing various options, like a fixed time on existing Starbase reinforcements, or the system we had in the previous blog. More details as we get them
  • This process is repeated for hull: when armor reaches 0 hit points, structure will become invulnerable for a specific amount of time after which hull will become vulnerable to attack

Repair state

Any damaged structure that is in a vulnerable state will automatically try to repair its shields, armor or hull after a specific amount of time. Unlike regular ship shields, this is not an on-going regeneration process – it’s like a shield booster or armor repairer that would instantly restore all hit points after a specific cycle time has passed. Please note this will not happen if the structure is invulnerable.

It will not be possible to accelerate the process using any kind of remote repair modules – we do not want to favor static fleets of logistics or carriers sitting near the structure and preventing incoming damage to be applied. In the same vein, we do not believe requiring players to sit for hours repairing a structure manually after a fight to be interesting gameplay.

This repair timer will automatically be paused whenever damage is being applied to the structure. This gives attackers a chance to take the shields, armor or hull layer down before the structures repairs itself.

As such, the attacker goal is to maintain a presence near the structure to keep applying damage over a specific amount of time until either the shields, armor or hull hit points reach 0.

  • As explained above, if shields reach 0 hit points, the structure enters an invulnerability phase, at the end of which armor will become vulnerable for attack
  • If armor reaches 0 hit points, the structure enters another invulnerability phase, at the end of which hull will become vulnerable for attack
  • If hull reaches 0 hit points, the structure is destroyed, its assets taken care by the asset safety feature

Adversely, the defender goal is to remove attacking ships doing damage to the structure before the HP layer is depleted (shields, armor or hull) – this can be done by assuming direct control of the structure, and / or by using your own fleet to repel the attackers (without the part where we give you a quick access route to the structure power core to blow it up with a few torpedoes, sorry).

  • As mentioned above, the repair damage stops whenever damage is applied. It will resume counting down 10-30 seconds after the structure stopped receiving incoming damage. When the repair timer hits 0, the structure fully repairs its shields, armor and hull
  • The repair timer will vary depending on where the structure is deployed, and if the structure owner has any kind of Sovereignty index
Repair timer for all Citadel sizes
High-security space and null-security space with full indexes 15 minutes
Low-security and W-space 30 minutes
Null-security space, owner has no index 60 minutes

Be aware that we are actively seeking to prevent types of hit and run tactics that would allow the attacker to apply damage without committing to the battlefield (we are looking at you, Stealth Bombers). If you want to attack someone’s assets, be ready to commit your fleet to it.

Anchoring or unanchoring a structure

For anchoring:

  • The structure goes into a 24 hour invulnerability timer. No damage can be done during that time and the owner cannot cancel this action once it has been confirmed
  • The structure will come out of the invulnerability timer with only its hull layer active and vulnerable to attack (enters the vulnerability states above).
  • As usual, any damage done to the structure while it is vulnerable will cause the repair time to start. Please note however that in this case the structure will only have hull layer available – it is not a fully operational battle station yet, and as such is even more susceptible to damage than usual. Which means if attackers can take it to 0 hit points it will be destroyed on the spot, there will be no further invulnerability phase.
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For unanchoring:

  • Unanchoring may only be started if the structure has full shields and is not within a repair timer. This is to prevent some early bail-out should it be attacked
  • Once the unanchoring process has started, the structure will become invulnerable for a specific amount of time
  • Once the invulnerability timers runs out, the structure will be vulnerable for damage yet again, with having a repair process identical of what’s been mentioned above. This time however, shields, armor and hulls will be fully available

Damage mitigation

Even if they’re not going to be directly involved any longer, we do believe Entosis Links promote beneficial gameplay in the sense they do create a more level playing field between various player entities: using an HP metric as an attack system alone strongly encourages blobs to pile up on structures. This in turn encourages us to create structures with lots of HP to make sure blobs take time to bring them down. Which removes any incentive for the smaller gangs to engage in structure assaults, thus reinforcing large blob attacks.

This is a vicious circle we intend to break while singing dirty French limericks and wielding a garlic-infused baguette. How? By introducing damage mitigation on structures.

The way damage mitigation is going to work is pretty simple:

  • We set a maximum limit on a structure, say, 4000 DPS
  • Every time damage is applied to that structure, we check all cumulated damage done before that within a specific time frame – let’s say 30 seconds
  • If cumulated damage on the structure would exceed 30*4,000 = 120,000 then any further incoming damage is reduced, or negated to preserve that amount over the last 30 seconds
  • Mitigation is counted after shield, armor or hull resistances are applied to incoming damage

Not all structures are going to have the same damage mitigation. That is going to vary depending on the structure size and role. Here are the numbers we have so far, along with some very rough calculations on how many ship types would be required to reach the indicated damage mitigation for each size (yes, those are very rough, no nitpicking).

Damage mitigation 4,000 DPS 12,000 DPS 60,000 DPS
Number of Frigates to reach damage mitigation 10-20 30-60 150-300
Number of Cruisers to reach damage mitigation 10-20 30-60 150-300
Number of Battleships to reach damage mitigation 5-15 15-45 75-225
Number of Dreadnoughts* to reach damage mitigation 1 2-4 10-20

*Assuming current damage numbers for Dreadnoughts, which may change with the planned capital rebalance

Structure HP numbers

As further iteration from the previous attack mechanic, we would like structure assaults to take around 30 minutes to complete, no matter where the structure is deployed. This ensures a unified experience and prevents confusion as a whole.

Based on the damage mitigation numbers above, we end up with the following HP and resistance profiles for Citadels:

Damage mitigation 4,000 DPS 12,000 DPS 60,000 DPS
Time to attack 30 minutes 30 minutes 30 minutes
Shield hitpoints 7,200,000 21,600,000 108,000,000
Armor hitpoints 7,200,000 21,600,000 108,000,000
Hull hitpoints 7,200,000 21,600,000 108,000,000
Shield, armor and hull resistances 20% 20% 20%

As a side note, there won’t be hull, armor or shield hardeners, or anything that increases structure EHP since we do not want attack time to drag on forever. There may be modules that switch the resistance profiles however, from, for instance, 20% EM / 20% thermal / 20% kinetic / 20% explosive to 0% EM / 80% thermal / 0% kinetic / 0 explosive.


We want the various timers and states to be visible to the owners and players partaking in structure attack, as such:

  • Owners with sufficient roles will be able to see the full weekly vulnerability window calendar. Corporation members without roles, or external parties will not. This information will not be publicly available throughout the API: we want people to actively scout or infiltrate the target corporation to know the most favorable moment to attack
  • Proper notifications will be sent whenever a structure state needs attention
  • As mentioned in the previous blog, all structures will have warpable signatures like combat anomalies. They will also show up in space / overview whenever the player can dock inside them
  • Timers related to the current state, or next available state will always be visible on the structure icon, in a manner very similar with the existing deployables. Of course, players not belonging to the corporation owning the structure need to be on grid to see them

Some examples:

  • If the structure is invulnerable, a timer will be shown counting how much time left before it is vulnerable again
  • If the structure is vulnerable, it will display for how long it is going to be before becoming invulnerable again
  • If the structure is being repaired, a timer also will be shown before it fully regenerates – if the timer is paused due to incoming damage this particular condition will also be displayed

Variations, general notes and you

There is a certain number of special cases we wish to tackle specifically in this blog, to avoid the recurring questions we’ve had in the past.

  • The current plan is for those structures not to have auto-defenses. This is still left to be debated, but we do believe existing auto-defenses on Starbases are nothing but a false promise to safety, since they are so easily abused and bypassed by attacking parties. They just give the owner a feeling of safety where none actually exists, like having a completely out-of-date firewall and anti-virus on your computer.
  • We revaluated our position on Wormhole space asset safety from our “I feel safe in Citadel city” blog. Structures destroyed in wormhole space will see all of their assets lost when destroyed and subject to the magical loot fairy rules that would normally apply for ship cargohold.
  • We are aware that the long process of sieging a Citadel (up to one week) is considerably longer that what’s currently in place in Wormhole space. We do know that controlling traffic in Wormhole space to be a taxing activity, which is why we are considering having further variations in place there so that the total siege doesn’t exceed 48 hours there.

Case study – the story of Croque-Monsieur Conglomerate™

The CSM requested we use an example to help illustrate the new attack system, which we thought was a good idea. We are going to start with a corporation owning a Medium Citadel in high-security space, the Croque-Monsieur Conglomerate™ (CMC).

CMC acquired a Medium Citadel structure and deployed it in Tar (0.8 security status system in Gallente space) at 18GMT on the 10th of September. As such, the structure will be invulnerable until the 11th of September at 18GMT, at which point it will become vulnerable for 15 minutes (located in high-security space), and only have hull as an active defense layer. An attacking entity who would have bothered to declare war on CMC and showed up might have been able to destroy, but that didn’t happen.

A Medium Citadel located in high-security needs to have 3 hours of vulnerability set up weekly. One of the directors of CMC, having enough roles, set them to Saturday, from 17 to 20GMT.

As such, the Medium Citadel will be invulnerable all the time, except each Saturday, from 17 to 20GMT, where shields may be shot. During that time, at 19:40GMT, an enemy corporation, the Implacable Kartoffelsalat™ (IKS), having a proper war declaration, shoots the shields.

As the structure has been damaged, it will now try to repair itself. Such a process would take 15 minutes in high-security space, which would bring end of repairs to 19:55GMT. Unfortunately, IKS keeps shooting the structure, which pauses the repair timer indefinitely. Since CMC is unable to repel IKS before the shields are brought to 0, the Medium Citadel enters an invulnerability phase at 20:10GMT, since it took 30 minutes for IKS to bring the shields down due to the damage mitigation mechanics.

Note the weekly vulnerability window would normally end at 20GMT, but was overruled due to the repair timer being active.

The Medium Citadel will stay invulnerable for a specific amount of time (again, how and when is still left to debate). Let’s say the Medium Citadel will come out of invulnerability 24 hours after the repair timer started, so 19:40GMT on Sunday.

As it comes out of invulnerability, the Medium Citadel armor is now susceptible to attack. As it is damaged, the Medium Citadel immediately starts a 15 minutes repair timer.

Since IKS doesn’t show up to damage the armor, the structure successfully repairs itself at 19:55GMT on day 2, causing all its shields, armor and hull to be fully repaired. Since there is no weekly vulnerable window set up on Sunday, the structures becomes invulnerable as soon as the repair timer runs out.

If IKS had shown up to damage the armor, the process would have been the same than for shields.

Final words

We do hope this new attack system will fulfill player needs more closely than the last version, while bringing more interesting fights and interactions around the new structures. Keep in mind this is still subject to change based on relevant feedback.

Our next blog will deal on how to build those new structures and which consequences this will have for your average industrialist or market trader out there.

Until then, may the odds be in your favor.

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