While bubble are indeed a fairly complex subject, the mechanics behind them are fairly simple once you get your head around it. In this post I'm going to explain the basics of how bubbles work, as well as some of the ways they you might use them. This article will focus on bubbles in general; I'm also working on an article specific to interdictors, which will cover some of the ways in which you can use these bubbles to your advantage.
Bubbles are a form of area-of-effect warp disruption which only work in nullsec. There are a few different kinds of bubble; the most common is the anchorable bubble (also known as a mobile warp disruptor), an object which can be launched and anchored much like a secure container and which will remain in position until destroyed. Bubbles can also be launched by both interdictors and heavy interdictors, which we'll talk about a little more later. While the method of producing these bubbles is different, the core mechanics are identical.
The most basic function of a bubble is to prevent ships from entering warp. Any ship which is inside the radius of a bubble (with the exception of tech 3 cruisers which have the interdiction nullifier subsystem fitted) will be unable to enter warp until the bubble is removed or the ship is has moved outside of the bubble's area of effect. If a bubble is put up covering the ship or a ship moves into a bubble while it is still aligning for warp, its warp will be cancelled.
The radius of various bubbles is as follows:
|bubble||radius t1||radius t2|
Drag and Catch Bubbles
In addition, bubbles can be used to intercept people exiting warp, causing them to land in the bubble instead of at their intended destination. These are known as Drag or Catch bubbles depending on their positioning relative to the gate (they may also be referred to as Pull and Stop bubbles, which are the same thing). Drag or Pull bubbles are positioned behind the object which you're warping to, while Catch or Stop bubbles are positioned in front of it, based on the direction from which you're warping.
|Obviously in practice having both on one gate would be pointless.|
- The bubble is on grid with your destination (regardless of distance)
- A continuous line drawn from your start point straight through your destination would pass through the radius of the bubble
|A catch bubble on the left, and a drag bubble on the right|
When you are caught by a bubble, you will exit warp roughly on the leading edge of the bubble. The momentum of larger ships will generally carry them well inside of the bubble itself, however smaller ships will often come to a stop just inside or even just outside of the bubble edge. Obviously if you do land inside the bubble, you will not be able to initiate warp until you get back outside of it. The point on the bubble edge where targets are expected to land is known as the 'catch point', and bubble campers will generally have a scram/web tackler or two sitting at this point to catch incoming ships, as well as jettisoned cans to decloak covert ops ships and other cloakies.
It's important to note that the exit point of your warp is determined when you click the warp button, not when your ship actually enters or exits warp. This means that if a bubble goes up after you've clicked warp but before you land, it will not catch you. Similarly if a bubble is up when you hit warp but subsequently goes down, you will still land as if you were caught by the bubble.
Drag and catch bubbles could be placed anywhere, however you'll most commonly encounter than on stargates. Note that they only work when positioned on grid with your destination, so bubbles anchored to catch at the gate which you entered from will not affect you. Again, t3 cruisers with the Interdiction Nullifier subsystem will not be caught by drag bubbles and will land at their intended desgination regardless.
Note that if the location that you're warping to is completely covered by a bubble, you will land at the edge of the bubble regardless of the direction which you warp from.
Anchored Bubbles, Dictors and Heavy Dictors
Anchored bubbles are fairly straightforward - they're launched from your cargo just like any other anchorable structure, at which point you can right click on the bubble and anchor it. Anchoring can take anything from 1 minute for a t2 small bubble up to 8 minutes for a t1 large bubble. T2 bubbles take half the time to anchor of their t1 variants, while each size of bubble takes twice as long as the next size down. These bubbles can be targeted and destroyed, and while large bubbles tend to be very tough, smaller bubbles can be killed fairly quickly by only a handful of dps ships. Providing it is not destroyed, an anchored bubble will remain in space until you choose to unanchor it.
Anchored bubbles make particularly good drag and catch bubbles, since they will remain in position independent of your ships, and since they're always up you don't need to worry about missing a target because you didn't get your bubble up fast enough.
Interdictor bubbles (also known as warp disruptor probes) function slightly differently - rather than being anchored, they are deployed instantly. Dictor bubbles cannot be targeted (although they can be destroyed by area of effect weapons such as smartbombs), and only last for 2 minutes; once their time is up, the bubble will simply disappear. Like anchorable bubbles, they will remain in position until that time is up. Interdictor bubbles are relatively larger at 20km, and due to their size and instant deployment they are very effective for catching targets coming through a gate.
Heavy interdictor bubbles are different again. These are projected around the heavy interdictor itself, and move with the ship as it travels (the heavy interdictor cannot warp or go through a gate while its bubble is up, nor can it travel particularly fast since the effectiveness of afterburner and MWDs is significantly reduced while the bubble is active). Like regular dictor bubbles the HIC bubble is deployed instantly, and it will remain active until the module is disabled (the HIC bubble generator has a cycle time of 30 seconds). Like regular dictor bubbles, the HIC's bubble generator is popular for bubbling directly on a gate.