Different special attacks will occur after destroying each heart on a Thargoid interceptor. Here is a breakdown of all special attacks and timings.
For detailed breakdown of Thargoid Attack values, visit out Thargoid Spec Sheet.
After the destruction of the first heart, the interceptor will begin to use its lightning when approaching within 800 m which will heavily damage your shields, render you immobile, and knock out your systems. Although your engines may still somewhat function, for a small period of time after the attack, you will struggle to build up speed as your ship will be under a braking effect, FA-OFF does not cancel out this effect.
After the second heart, the interceptor will use caustic missiles, which are slow-moving (~350 m/s) missiles that applies a permanent DoT (damage over time) on your hull. Caustic Damage can be removed by bringing your heat above 180% for several seconds, or to 250% for instant removal, or by using a decontamination limpet. To achieve these temperatures, you can use SCBs, firing gauss cannons, or if you can afford to drop shields, using silent running.
Ensure you have sufficient heatsinks/power in sys to fire two heatsinks to quickly bring your heat below 100%. During this time, the interceptor will not miss. Alternatively, caustic damage will be removed upon docking at a station. The launch of caustic missiles can be entirely avoided by keeping a low temperature (below 20%) or being outside of 3km. Decontamination limpets can also be used to remove caustic, however note these can be the slowest method and require limpets in cargo.
On the second-to-last heart, the interceptor will use EMP (shut-down field), which will render your ship inoperable for 30 seconds or so (your wing beacon will also turn off because of this). You can avoid triggering the EMP field by being outside of 3 km before it attempts to initiate the attack, or by keeping a low temperature (below 20%). You cannot avoid the EMP once the attack has been queued unless you are beyond 10 km, stay in FA-off and boost away from the swarm/interceptor before the attack hits if you are not carrying a shutdown field neutralizer.
With the exception of the lightning attack, once the thargoid has deployed the swarm you are not in danger of being hit with the special attack. (Unless you experience the Heart Cycle Reset Bug)