Game:Tidus, Selphie, and Wakka
Tidus, Selphie, and Wakka are Sora's three friends on Destiny Islands, and are a set of optional bosses found in Kingdom Hearts. They ask Sora to have practice fights with them on the first and second days on the island. After defeating each of them individually, Sora can ask to fight all of them simultaneously. Tidus is also a mini-boss in Kingdom Hearts coded and Kingdom Hearts Re:coded.
Tidus is slightly stronger than Selphie and Wakka, but the match is simple. In a similar style to Sora, Tidus fights using a stick. He will be constantly attacking Sora head on throughout the fight, so don't give him an opening. The best way to defeat him is by dodging his strong attacks and trying to jump behind him. While still in the air, attack him with an aerial combo. Try to parry his attacks by striking at the same time he swings, doing this not only grants Tech Points, but will also stun Tidus long enough to deal one or two combos without interruption. Also, if Sora runs around avoiding his attacks, he'll get tired and begin complaining for a few seconds; this leaves him open for a quick combo.
Selphie fights using a jump rope attacking from a short distance. She is the fastest out of the three, but her attacks are easy to block and counter. Unlike Tidus, she tends to run around Sora or jump away before attacking. Deflecting her jump rope earns 1 Tech Point. An extra point can be obtained if the jump rope hits Selphie's head in the process. If Sora fights only by deflecting Selphie's jump rope, her HP will be reduced to 1 and will not decrease any further, making it a good way for Sora to gain experience before dealing the final blow. Be careful in the battle, as it can be difficult to see her jump rope and she could land an attack if you are not careful.
If Sora is battling her alone, simply lock on to her and attack. She will fall with relative ease. Be sure to avoid her attacks as they can stun Sora leaving him open to attacks. However, Selphie can leave herself wide open for counterattacks; deflecting her attacks will stun her for a few seconds, and sometimes she stumbles when she's leaping.
As more of a ranged fighter than the other two, Wakka will try to keep his distance before throwing his ball at Sora. If timed well Sora can hit the ball to deflect it back at Wakka, this will grant 1 tech point. Occasionally, Wakka will launch a faster and stronger ball, preceded by a jump and yelling "Take this!". If Sora hits it, 2 tech points can be gained, making the perfect enemy for early experience. This is the best time to strike, as he is basically defenseless. However, watch out for the ball he will throw randomly while he is stunned. Take this time to use ground and aerial combos on him. At close range, he will do a spin attack on Sora which is fast and hard to block.
Tidus, Selphie, and Wakka
When fighting all three, the main strategy to use is to take out the characters in a certain order. It may be wise to defeat them in the following order Tidus, then Selphie, and last Wakka. Wakka's attacks are easy to dodge, so save him for last; also, if Selphie or Tidus are not much of an issue, Sora can gain more experience by hitting Wakka's ball. Selphie can be annoying when trying to fight Tidus; if she is giving Sora trouble, consider defeating her first since she lacks defensive abilities. Tidus should be the fist priority, due to him having higher defense and attack than Selphie or Wakka. It is unwise to save him for last, as he'll be constantly rushing at Sora, and can attack him repeatedly while his attention is on the other two.
Another strategy is to try to use Wakka's ball to hit Tidus and then take on Selphie. To do this, lock on to Tidus, then move around until both he and Wakka are in Sora's sight. Continue dodging attacks and moving while keeping these two in sight. When Wakka throws his ball, hit it. If Sora is locked on Tidus, the ball will automatically fly at him. The hit will stun Tidus for a while and deal damage. This will allow Sora to focus on attacking Selphie. If she was already defeated, one can continue to hit Tidus with the ball until he's defeated. Then you can fight Wakka either by hitting the ball back at him or simply using normal attacks. Upon victory, a Potion can be gained.
Kingdom Hearts Re:coded
Tidus's attacks are really simple and are easy to dodge in Kingdom Hearts Re:coded. He will run towards Data-Sora and either do a flip while slashing his stick downwards, or just slash his stick downwards. Although the attack can deal damage, if Sora successfully avoids it, Tidus will be vulnerable to attacks. Dodge Roll is recommended to avoid those attacks, but the best strategy is to lock-on, run around, and attack after he strikes. On normal visit, defeating Tidus will reward Data-Sora with a Potion.
On Questploration, Tidus's stats are increased, but his move set is still basically the same. Aside from gaining 409 exp, there is no reward.