Gym Battlesgym Battles
Should a pokemon gym be held by an opposing team, you will have the opportunity to battle it in hopes of eventually removing all of the Pokemon currently found at it so you can claim it for your own team. gym Battles remain relatively as like the former Gym System, as all Pokemon Moves are practically automatic. If you tap the opposing Pokemon, your Pokemon with attack with what are known as their Fast Attack. As the opposing Pokemon is attacked and its Hit Points are lowered, your Pokemon will charge meters in order to unleash a much more powerful move known as a Charged Attack. You can also dodge your opponent's attacks by swiping to the left or to the right. (There is also a set timer that a Gym Pokemon must be defeated within, or else you'll be kicked out of the Gym.)
When you challenge an opposing team's gym, you can select up to six Pokemon to battle it, which, in turn, can have up to six Pokemon of its own within it. (The game will automatically recommend six of your Pokemon that match up well against the opposing Pokemon, but you can easily change these picks by clicking on them.) Since this number was reduced from ten Pokemon to six Pokemon from the previous Gym System to the current one, you have a greater chance at winning when you do decide to take on a Gym. If other players in your team or the third team not in possession of the Gym join you in your efforts at defeating the Gym, this further allows stronger Pokemon Gyms to be more easily defeated as teammates will also appear in Gym Battles and attack the opponent as you do.