I see a lot of requests for Guardians of Graxia impressions...I bought it at $5 a day or two ago and have put a few hours into it, so I'll do my best. This is based on the first few campaign missions...I haven't tried skirmish yet. My account shows 30 minutes played but I've been on a train so I have a lot of offline playtime unaccounted for.
The game makes a really bad first impression. I had to turn the detail wayyyyy down on my laptop to get it to run at all, and it's still kinda choppy (think Sims-style choppiness; no matter what you do there will be some choppiness). I expect it to run much better on my PC at home, but I was surprised that an indie title in this genre would have so many issues. There's a lot of unnecessary animation on the field which I'm sure contributes to this. I remember reading in a review somewhere that it looks much better than most $10 games...I disagree with this statement, and I would suggest that its poor optimization sorta makes it a wash anyway. For comparison's sake, this computer can run Starcraft II with low-to-medium settings without dropping frames at all.
To make matters worse, the tutorial doesn't explain nearly enough about the game's many statistics. You will spend your first few games a little frustrated when you make a move that looks like it makes sense only to find that the enemy unit you are attacking has so much defensive support it cannot be harmed. I feel like I'm starting to get the hang of it; it sort of reminds me of my experiences with the GalCiv series, in that the information is there, it's just a little hard to put the pieces together and wrap your head around it.
I haven't really figured out how the decks work yet either; it seems like in the campaign you either earn cards or change decks; there are different cards in the second campaign mission but no explanation as to why. I had thought this would be sort of a SRPG with a little M:TG thrown in but this doesn't appear to be the case, unless things change down the road.
Fortunately, the gameplay is actually pretty fun. You move characters around a game board, swapping turns with your opponent; this basic structure should be familiar to strategy game fans. Your opponent's objective is to kill your team's Guardian - the most powerful character in your arsenal, though the power difference between it and regular units isn't so far off as Demigod or anything like that - and each campaign mission will present two available objectives. If you complete either objective, you win, and if you manage both within a certain period of time, you earn a "Guardian" rank for the level. It's fun enough that going a few rounds with some friends whose understanding of the game's mechanics are about as limited as your own would be a lot of fun. Too bad there's no multiplayer, then, right? On the other hand, I've been very impressed with the AI in the campaign; this might be an effect of the AI having a better understanding of the game's rules than me, but from what I've played it does seem to make tactically sound decisions. This is key for a game with no multiplayer, of course, and I'm looking forward to fiddling with it in the skirmish mode. It does seem to turtle a bit too much, and this might be an issue in the skirmish mode. It works for the campaign, though, since you only have a few turns to complete your objective.
When you first start the game, you'll see a tutorial, five campaign missions and four skirmish missions...and there doesn't appear to be much more than that. This is my big issue with the game - there's no random map generator, no custom maps, and no multiplayer. The gameplay is pretty good and the AI is impressive, but with so few maps the game's replay value is inherently limited (though each of the campaign maps has a "normal" objective and a "hard" objective which is genuinely difficult to achieve). The UI appears set up to add additional campaigns and guardian decks, but that's all speculative. I would have been pretty unhappy if I had paid $10, but I'm content at $5. $2.50 is a good enough price for any strategy fan, just be aware that your hours-per-dollar on this one isn't going to come close to many of the other games selling for the same price during the sale.
Best point of comparison for gaffers: Culdcept, though this isn't half as good.