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In Pokemon XD, Pokemon trainers have their Pokemon battle each other. Since you will be doing this constantly throughout the game, read through here to learn the basics.

First off, each of your Pokemon know attacks, they may be able to directly damage the opponent's Pokemon, such as Tackle, or they may be moves that hinder the opponent's ability to fight, such as Sand Attack, which lowers the opponent's accuracy.

You can also use items you buy at Pokemarts during battle; they range from medicine to power-up items.

Also, you can switch your Pokemon with another Pokemon you have with you. This is useful for when you need to get one of your Pokemon out of the battle.

Moving on now, Pokemon are catagorized by type. We have fire pokemon, water pokemon, electric pokemon, and so forth. Pokemon attacks also are catagorized by type. Types work in a Rock-Paper-Scizzers fashion; Fire beats Grass, Grass beats Water, and Water beats Fire. If you use an attack that is Super-Effective against the opponent's Pokemon's type, they receive double the damage you would have done to them. Also, in Pokemon XD, we have Shadow Pokemon that are Super-Effective against all types of Pokemon and are resistant to other Shadow Pokemon.

Also, be aware of what are called status effects. They cripple your Pokemon in some way. here is a list:

Poison. Drops a Pokemon's HP each turn.

Paralize. Slows a Pokemon and might prevent them from attacking.

Sleep. The pokemon sleeps helplessly for two-to-five turns.

Burn. The Pokemon's attack stat is halved and they lose HP each turn.

Freeze. The Pokemon is frozen helplessly for one-to-six turns. Fire can thaw them out.