StancesEach person automatically uses a stance when fighting. But it's the type of stance that is always the key in battling. It's the type of stance that could tell you what move the oppoment is preparing. It is also good to know about 'trick' stances too. Oppoments may slide into a stance, hoping to slide into another, once you have made that fatal move...
A basic stanceThe tricky thing about stances, is predicting them. People usually use stances that are easiest to do, and help strengthen their attack. For example. The picture above, could indicate an Earth element being played. Although many people do not bother to learn it, it can be quite powerful to break another person's stance. The person in the picture, has their arms in front, and their right leg, (the one on the left
xd ) bent in a strong position, the left leg isn't bent as strongly. So the person is most likely to use it's left leg for a kick. The arms are in a defensive stance, so are not very likely to attack, since the left leg is looser. The person is likely to stamp the ground, and use the arms for concentration, to direct a force from the earth, to send to the oppoment(s).
But it is very useful predicting a stance. If you can predict for example, that the person is going to use an Earth move, you can time the attack right, and leap out of the way - just in time! Then quickly attack the person, as the person used great concentration on the failed Earth move - and it was wasted!

This person, has a very bent right arm. This defently shows a defensive stance. The left arm looks like it will be used for balance. Balance is also a key in stances, and is useful to tell if it's a trick stance or not. The right leg is fairly straight - also for balance, and the left leg is also straight. But if you look carefully, you will realise that attacking directally isn't a good idea, because the left leg and the left arm is in a position where they can move quite quickly. The person could swing the left leg, and the left arm, use it's right leg to balance it self, until lift of, where you would be likely to miss your move. Due to gravity, the person could take avantage of it, and spin it self rapidly, so it is facing the same way you are, but be behind you. And so, the person will be able to attack you from behind, and you will not be able to defend. Knocking you down.
It would be a good idea to attack from behind. But be careful, as the person can easily swing and face you. Try aiming to unbalance the person. I would probably (if it isn't night time and Tulin is very tired.) , slide right under the person, and launch a hard kick under the person, where there is a lack of defence. This will cause the oppoment to lose all type of stance, and once it has hit the ground, it will be easy to attack as soon as it gets up. But it might be able to recouperate, and return it's stance when it gets up. So make sure it is a really hard kick
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Now this person is in a dangerous stance. For itself and you. Attacking it at the front is a bad idea. It's arm and leg behind will easily be able to counter attack - harder. Attacking from behind isn't the best idea either, since it appears the person can easily flip, and face your way, but before it lands it could swing a kick at you.
Sliding under the person isn't a good idea either, as the person could quickly swivel, from a leg, and get you as you miss a fatal attack.
Using an elemental launch attack isn't the best idea either. Because it is very likely to miss. The person will also have an advantage in aiming and concentration too.
A good idea is to concentrate yourself, and be ready to avoid whatever gets thrown at you, then quickly attack as the move is missed. The person is likely to use of a fair amount of energy - that you can use to your advantage.
There is plenty of other stances you can use to. So, it could be a good use, if you describe your stance that you use, and remember them more often. It could add a good addition to any fight.