For now, I've updated the ion cannons article - there was a bit of editing but primarily I updated the article with a section on Heavy Ion Emplacements:
|Remember, kids: recreational taser play while piloting a starfighter is bad news.|
Heavy Ion Emplacements
- The effect only resolves if you have a blue critical icon showing when the time comes to choose your critical effect.
- Heavy Ion Emplacements exhausts upon use, which means it can only be used once per activation (as it will be exhausted when used the first time) and can't be used at all if it has been exhausted preemptively by something like the MS-1 Ion Cannons.
- You must apply as much of the card as possible, so if an eligible hull zone is missing shields, then HIEs won't affect that particular hull zone.
- Don't forget you always have the option of using the default critical effect if you get a blue crit but your target has few to no shields remaining.
- Because of the timing order, HIEs trigger before damage in the pool is applied, which can have consequences for redirect tokens and how much hull damage gets through the suddenly-reduced shields.
Because it's a critical effect that adds three damage. There aren't even any black critical effects that directly add three damage to whatever they are targeting, and Heavy Ion Emplacements can even trigger from long range when used with effects that add blue dice at long range (like Quad Battery Turrets) or when your blue dice range gets extended from Disposable Capacitors. HIEs can add a lot of extra damage over time, but it's important to realize that you'll really only want one or two in a fleet because the more effective they are at removing shields, the less effective they are in future attacks against targets with depleted shields: they're effectively an upgrade that shines brightest in the early-to-mid-game, but there's nothing wrong with being good at softening up targets for easier destruction.
Heavy Ion Emplacements have competition from other ion cannon upgrades, particularly the "standard" SW-7 Ion Batteries and Leading Shots, which are generally better for smaller double-arcing ships (SW-7s) and larger mixed-dice battery ships (Leading Shots). Heavy Ion Emplacements can act as a replacement for SW-7s on ships like CR90Bs or Interdictors, provided the player is comfortable with gambling a bit on the effect triggering or (more likely) has a commander that can assist with rerolls or guarantee critical results, like Commander Leia (concentrate fire to add a die and reroll), Commander Vader, and Admiral Screed. On larger ships, they can replace Leading Shots when used with similar commanders, provided you feel comfortable giving up the "bad dice insurance" of Leading Shots in favor of something that produces more raw damage when you get the critical.
Heavy Ion Emplacements are particularly appealing on small and medium ships with offensive retrofit slots that are already keen on using Disposable Capacitors, such as Raider-IIs, Interdictors, and VSD-IIs (usually if that VSD has some kind of dice-control commander). Disposable Capacitors and HIEs synergize very well in that they will often let the expensive HIEs start triggering one round earlier, helping to subsidize the high expense of the upgrade, but also because long-ranged attacks are often made against targets that are still pretty healthy, increasing the chances of the HIEs triggering for full effect. The Raider-II in particular is a big fan, because it generally did not gain as much from SW-7s as its CR90B cousin and it previously lacked a strong ion cannon upgrade: with one strong arc (so it doesn't matter if HIEs only work once per activation) and access to Disposable Capacitors on the cheap, the Raider-II seems designed to cooperate with Heavy Ions.
The last thing I'll add to this review is to understand the importance of target selection with your Heavy Ion Emplacements: the upgrade is stronger against ships with redirects (as it not only depletes a shield in the arc you're targeting, but also in both arcs the damage can get redirected to) and weaker against ships with evades (as if you can't lock down the evades or produce more than one blue critical result, the blue crit die will likely be rerolled into a non-crit or removed from the pool altogether). This means that in general, you should be looking to go after bigger ships with your HIE-equipped ships.