As I've been telling people, it made the most sense for the first Deluxe Expansion for Conquest to be solely a Tyranid one- adding Necrons in would dilute the Tyranid card pool too much, and with Tyranids unable to take allies, they needed an earlier start than the Necrons. As such, I'm pleased to see FFG announce that the first Deluxe will indeed be Tyranids (with a few other cards from the other factions). So let's have a look at the cards:
Man, lots going on here. First, the Tyranids are introduced, obviously, and come with a new type of unit- the Synapse unit. In the 40K game, Synapse units are there as a means to extend the will/control of the Hive Mind, and better direct the individual units on the ground. Now, having Synapse units die in the tabletop game wasn't a particularly good thing- something I hope has some parallel in the tabletop game. Here, all we know is that the Synapse unit will work like a second warlord, with different effects, depending on the unit (five Synapse units included in this expansion).
We also know the Tyranids will do something with infesting planets, which will trigger additional effects, like with the Hunter Gargoyles. These infestation tokens can be removed by winning a combat at such a planet, so the effect is reversible, at least. We're not told specifically if Tyranids have a different win condition (they aren't interested in Tech, Strongpoints, and the like, the article specifically calls out). I wonder if the Infestation idea will tie into their victory condition, if they even have a different one.
The Termagant is a new token unit that can get bonuses from cards with the Hive Mind specialization, as seen on the Termagant Spikers. Having Tokens that gain new abilities is really cool, and I think that's a great place for additional design space for the Tyranids.
We also see a hint of another Specialization on Roghrax Bloodhand: Bloodthirst, which seems to trigger when an opponent's unit has died in a combat at a planet. Another cool way to do things- this doesn't really add new Keywords to the game, but instead gives a way to add related abilities to a variety of cards that could be interacted with later (say, a card that turns off all Bloodthirst specializations for a turn).
For the Tyranids, it's a bit too early to tell how good their cards will be without both their rules and many more examples of their cards. The Warlord/Synapse pair previewed is certainly exciting enough, but it's still going to be several months until we see these on the table. So far, they seem to be a bit light on Command Icons, but we definitely don't have the full picture yet.
Pathfinder Shi Or'es seems like he'll be a good help to Tau. Three Resources for a 3/3 with 1 command icon is a pretty good deal. His ability will be nice in a Shadowsun deck, where you're able to recur Attachments, but may actually be of some use in an Aun'Shi deck too- even dropping an Ion Rifle off him lets me put out a total of 9 Armorbane damage in one combat, which is terrifying. I could see him having a place, without a doubt.
Seraphim Superior Allegra is both a joy and a disappointment to me. First, she's going to be incredible for that support heavy AM build that they seem to be trying to push. Putting Catachan Outpost on her, having her attack, and having that Catachan Outpost available again is REALLY effective. And there's no shortage of great Supports that could see play in a deck using her (at 4 cost, using this to power Staging Ground would help offset her cost, as well!). She's going to see play, without a doubt, I think.
I'm a tad disappointed, however, because she's the first Sisters of Battle army unit out there... and they didn't give her any traits. No Sisters of Battle (or Adepta Sororitas) trait, no Order of Our Martyred Lady trait (based on her uniform). Nothing. Just Ecclesiarchy. Perhaps I was wishing too much, but as a former Sisters of Battle player, I would definitely have loved to see some love for them. Her inclusion is a start, but I would have loved more.