|My asthma's acting up like crazy, my BDSM space samurai wizard outfit has terrible insulation, and it's blinding white everywhere. Hoth is the worst!|
- Tenacious V's ability only works on ship versus ship attacks. You cannot use it while attacking squadrons.
- It's a "while" ability, which means it tells you when it triggers and that you can do it one time during that window. You can't keep spending defense tokens to keep rerolling dice.
- Spending a defense token works the same way as when you use it defensively - a green (readied) defense token turns to red (exhausted), a red defense token is discarded.
- Vader's ability works during the Resolve Attack Effects step, so don't forget to use any effects that add dice (such as concentrate fire) prior to using Vader's ability - you can reroll any added dice that turn up blank (as well as your initial volley), which is quite helpful.
- There are 4 different versions of Darth Vader in the game (dude gets around), and remember that you can't have more than one in any given fleet. So no Vader commander and Vader boarding team, for example.
Darth Vader is one of the most expensive commanders in the game and he can be tough to fit into fleets. Using his ability can leave ships exposed to problematic situations when they're attacked by enemies later in the turn - if, for example, you really want to redirect an attack but your only available redirect is already exhausted due to Vader, you get to choose between "eat that damage you didn't want to eat" and "pitch a token for defensive purposes, making Vader's future uses even more unpleasant for you now that you have less defense tokens." It's a bad feel either way.
That's not to say it's all dark sides (boo! hiss!): Vader's reroll ability is the most generous in the game, allowing you to reroll as many dice as you please regardless of range or type of dice or having to do anything other than be attacking a ship and spending a defense token. The benefits in particular to red dice are quite notable, as red dice are generally unreliable and thus upgrades that allow you to set or replace even one of them (like Turbolaser Reroute Circuits or Linked Turbolaser Towers) are highly valued for that reason. Vader lets you reroll all of them if you so choose. Any dice can benefit, of course, and depending on the ship in question Vader can be useful for differing purposes - ships with a lower supply of blue dice can use Vader at least in part to go fishing for otherwise-unreliable accuracy icons, for example.
|It helps if you announce clearly when you're using Vader's ability.|
Given the ubiquity of other dice rerolling tech, most commonly Leading Shots and Ordnance Experts, Vader is especially handy for ships that either can't take those upgrades but want the dice fixing or would like to equip something else in that slot instead to further increase their offensive output without having to sacrifice attack reliability to do so.
So with all that said, what exactly should one be looking for in a ship that Vader wants to run?
The first thing to look for is expendable defense tokens. By this I mean preferably 4 defense tokens total but at the very least your standard 3 with two of them being the same type. Contain tokens are generally the easiest to spend for this, but circumstances can make other types more or less appealing.
The second thing to look for is red dice. As mentioned earlier, Screed generally does a better job with black dice ships than Vader does, but in addition to that, all Imperial ships with more than 1 black dice have weapon team slots, which means if you're just rolling a big pile of black dice, Ordnance Experts can give you the rerolls you crave for a very competitive cost and no defense token spending downside. Once you add in red dice, though, those become more difficult to reroll reliably, especially at long range. Leading Shots helps but only once you can get your blue dice into the mix.
So what type of ships meet these criteria to some degree or another?
Imperial-class Star Destroyers are the go-to choice given Vader comes packaged with them. Every ISD is happy for the reroll, but that's especially true of the Cymoon, which packs a strong long-ranged punch but lacks an ion cannon slot to equip Leading Shots for the kind of dice control you can rely on. Otherwise, Vader is a solid choice for ISD-Is looking for easy access to rerolls (as Leading Shots is a bit awkward for the no-blue side arcs) and ISD-IIs that want to improve their damage reliability at long range and want to increase their damage output by using a stronger ion cannon instead of Leading Shots. Kuats can equip Ordnance Experts and/or Leading Shots so generally they're not in need of what Vader provides as much as the other ISD variants.
Arquitens are a great choice with Vader given their red dice focus, expendable contain token, and lack of easy access to dice-fixing. Intel Officers are a solid officer choice for Vader Arquitens, plus some turbolaser method of adding an additional die.
Interdictors are typically looking to trigger their blue crit upgrades for the extra damage boost they desperately need and have two contain tokens to spend, making them an easy inclusion with Vader.
Onager Testbeds are just one big gun mounted on a chassis that doesn't really want to get exposed to too much heat and has a salvo token but a pretty poor salvo (one black die against a squad or a mediocre red+blue against a ship). They also don't have super reliable dice control. Vader lets you run them fairly upgrade-light by filling in for the dice control weapon teams if you need him to, and the Testbed doesn't mind spending its salvo token for his reroll.
Victory-class Star Destroyers, especially VSD-Is, appreciate the help with their red and black dice. It's often not worth equipping Ordnance Experts given your default VSD-I doesn't get a lot of close-ranged attacks in, but it really sucks when you finally do get your opportunity and the dice just won't behave. Vader helps get your long-ranged attacks as well as your big salvos to stick without having to equip a confused weapon team that usually won't do much. That said, be careful here: VSDs don't have an easy contain to spend and using Vader's ability more than once per round can put too much pressure on your defense tokens.
Otherwise, pretty much any combat ship is worth considering, although the synergies may not be as strong. Raider-IIs, for example, appreciate the extra help sticking their blue crits without having to equip a weapon team to help, but the combination doesn't fundamentally change the ship. On the other end of the spectrum, SSDs have two contains to spend and can put out withering firepower at long range that they want reroll help with, but Vader spending their defense tokens can put too much stress on the defenses of a centerpiece ship your opponent is trying to gang up on. Both of these do fine with Vader but I wouldn't call them a strong synergy.
Similar to other commanders like Screed that only really work their magic on ships that want to fight, Vader isn't too keen on bringing along a lot of squadrons. Therefore, his fleets tend to bring zero to few squadrons overall so you can recoup your significant commander investment by applying his buff to several combat ships. The decision there comes down to how comfortable you and your fleet are with completely ceding the squadron mini-game to your opponent.
Your standard Vader fleet usually lands somewhere between MSU and Big Heavy, depending on how much you want to rely on heavier more expensive combat ships compared to more numerous small combat ships. A pleasant in-between is your standard LMSU fleet, which can work very well with an ISD running a fleet command (either because it's a Cymoon or you're using the Chimaera title) to help with navigating, usually Entrapment Formation or Take Evasive Action. Vader covers your attack dice, the fleet command helps with navigating, and you have a lot of flexibility in how to use your fleet with two different force multipliers.