The anticipated mobile augmented reality title Pokemon GO's field test is well under way in Japan, and the dedicated folks over at /r/TheSilphRoad have revealed even more about the tests including some more about the games' content. This particular subreddit was also behind the major leak in late March when the downloads were first sent out for the Japanese field test. Recently developer Niantic implemented Gyms in their field test, while players started tracking exactly where certain types of Pokemon can be found. They are also now answering common questions about how certain mechanics like training, biomes, and the Gyms will function. A lot of the leaks also include hints that may come in handy when the game is finally released, like patterns on where to find Gym portals.
Earlier in the week Gyms were enabled, allowing field testers access to them for the first time. This also opened up the ability for players to join teams (currently labeled Red, Blue, and Yellow, after the original Pokemon games). This was also the first time testers could use some of the battling features. Unfortunately there are no screenshots or video available - /r/TheSilphRoad says they do not have permission from the players to release a combat video. But the hefty description is enough to give players a good idea of how things will work.
Rather than the games, which have set gym leaders, gyms in Pokemon GO are, of course, run by the players. If you come across an empty one, you can leave a Pokemon to defend it. Then you can battle against your guarding Pokemon to train it. One of the biggest reveals in this is that it appears training and possibly all combat will not be turn-based. Instead you duke it out with the opposing Pokemon by either tapping or pressing and holding the screen, depending on the attack. You can slide left and right on the screen to dodge. How much you can attack is based on your stamina, which increases faster when you're hit (like to avoid outright abusing the dodge mechanic). Battles have a 120 second timer, but most battles end in under a minute. After training, you need to heal your Pokemon with items - as of yet, there don't appear to be PokeCenters. As you train, you gain Prestige which increases the level of your gym and helps protect it against players from opposing teams. It's worth noting that /r/TheSilphRoad reports an enormous difference between Pokemon GO and Niantic's other augmented reality title, Ingress, in both animation and mechanics.
If you encounter an enemy gym, you can take six Pokemon into battle which are randomly select (at least for now). The Gym Leader at the time will have their avatar prominently displayed. You have to defeat a gym multiple times in order to return it to "neutral" and claim it for yourself. If in the midst of battle a Pokemon faints, the 120 second timer keeps going so it seems to be based on the opposing Pokemon, not your own. And keep in mind - types still matter.
A later leak published on April 14th, answered some more questions about the combat. There is apparently no cooldown on training so players could potentially train endlessly if they wanted to. Once you deploy a Pokemon to a gym though, you can no longer have it in your party or use it elsewhere. It is stuck there until the gym is defeated. There is a distinguishable pattern for finding gyms - consider what most gyms in the game look like, typically extravagant and important looking. The same concept carries over here, with large parks, libraries, and churches being common places for them to pop up. There is no sign of PvP combat yet, and testers say they haven't heard when it will be enabled.
There has been ample time to test the mechanics for catching Pokemon however. Rather than battling wild Pokemon, you simply have to catch them. Wild Pokemon vary in capture difficulty of course, and finding them is not a simple task. While some players have been able to find Pokemon you couldn't normally find in the wild, like Flareon, others have found that even simple types are difficult to get your hands on. Water Pokemon especially seem to be spawning in the middle of lakes and rivers, where obviously not many players will be able to reach (unless your phone is a legendary level of waterproof). Other types are a bit easier to get to and catch. No sign of any legendary Pokemon yet, though decompiling of the code has indicated they are definitely out there.
There is still no solid release date beyond "at some point in 2016" for Pokemon GO anywhere (the March GDC session hosted by Niantic where many expected the date to be revealed was cancelled with no cited reason). There will however be another field test this time for those in Australia and New Zealand who wish to participate (you can sign up here - keep in mind this link only works if you actually live in Australia or New Zealand). More field tests in Europe and North America will likely be announced soon.