The gameplay uses the concept of simultaneous play, unlike most TCGs. Usually one player takes their turn, then play switches to the other player. In Infinity Wars, both players set up their planned actions, then the game resolves the actions simultaneously. This adds a bluffing aspect to the game that isn't present in the traditional turn format - should I send creatures to defend against my opponent, send them to the attack, or keep them back in the safer support area? Should I cast this ability card that only works on attackers against an opposing creature this turn, or do I expect my opponent will be using that creature on defense? The simultaneous resolution adds depth to the decision making that isn't present in many TCGs.
Another interesting gameplay mechanic is the use of "commanders," which are three cards that you choose to reveal at the start of the game and put in a special command zone. They're playable from there, and the identity of your commanders determine which factions you can use in your deck. Having three cards that are always available from the beginning of the game really influences how you construct and play a deck. It allows you to set up strategies that wouldn't be possible if you had to rely on the right cards coming up in the usual random draw. Of course, there are cards that allow your opponent to disrupt your plans for those commanders as well.
Infinity Wars has two major play modes, constructed games and a limited format called "Rift Runs." Constructed is pretty much the same as any online TCG, with casual and ranked play modes. The game provides several pre-constructed decks that newer players can use, which is a nice touch for those without extensive card collections. Those decks won't have much chance against experienced players, but they're generally fun to play and have coherent themes that a newer player can use as the basis for building their own future decks. The Rift Run format works by choosing one card at a time from random sets of three, until you have a full deck to play. You play games against other players' Rift decks until you've lost three times. Not much different from other online TCGs with similar formats, such as Hearthstone's Arena mode.
Like many online TCGs, Infinity Wars uses a free-to-play business model, but it's not very well implemented. There are two tiers of currency, one earned through play time and the other only available by spending money. Very little of any value is available via the free currency. Entering Rift Runs is about the only thing worth spending points on. The runs themselves can be fun, but the rewards are so paltry that you won't make much progress on a card collection. There are some minor daily rewards for logging in, but no daily or weekly quests to entice players into coming back regularly. If you do spend money in the store, the prices are high enough that you'll need to outlay a good amount to get a significant card collection. It's possible to play without spending much money, but only at the level of a couple of Rift Runs per week and very simple constructed play, and you don't feel like you're making any real progress toward a higher level of play.
There are quite a few technical problems with Infinity Wars. Simply logging in can take a good long time, both in making an initial connection to the server and waiting for it to process your information after logging in. It often takes several minutes of searching for an opponent to start a game (in either constructed or Rift mode). Since the game starts as soon as an opponent is finally matched up, you can't go do something else while the search is on, resulting a lot of time spent staring at the screen while waiting on the game to finally start. The Rift matchmaking is particularly bad, often pairing you with the same opponent in consecutive games, which is truly annoying if you just lost badly to that same deck. I've also had several disconnections in the middle of games, either causing game losses (if it was on my end) or causing me to have to wait for my opponent to time out (if it was on their end).
I like the concepts behind Infinity Wars, particularly the mechanics of the simultaneous turn planning. It's too bad the technical and business model aspects of the game aren't particularly well implemented.
