The Arbiter is a unot with many talents not the least of which is turning the tide of a battle. Not with brute firepower like a Carrier or with quiet sneaky attacks like a Dark Templar but with energy attacks that are able o cause havoc. The Arbiter has two attacks that you can choose to upgrade and you can also choose to upgrade the Arbiters energy capacity by fifty. the arbiter has a rather weak cannon capable of shooting both air and ground units but it is best used with these attacks.
Recall, Recall will move all units within the Recall range to directly under the Arbiter that used Recall. This can be effectivly used if your Arbiter is close by or over an enemy base and you use Recall on a large cluster of your forces. If your forces are not clustered not as many will be moved.
Stasis Field, Stasis Field will temporaroly freeze ANY units (this includes yours) caught in the attack in a Stasis Field. While they are in this field they are unable to attack or be attacked. this can be effective if you have a large force attacking your base and you use this on half the force then you can kill half they're force and then kill the other half rather then kill the whole thing at once..