The Arts in this game are comparable to spells, techniques, or powers from games like World of Warcraft or Aion. Separate from your Auto-Attacks, these are the abilities that make your characters distinct and define their roles perhaps even a bit more than their stats and Skills do.
Arts have a variety of effects that are suited to the characters who wield them- damaging and debilitating effects from your DPS characters, and attention-grabbing or party-buffing effects from your Tanks. Many arts will inflict conditions like a loss of Defense or Attack Power, or will boost your characters with added Ether Power or even restoration of Hit Points or Talent Art gauge. Some arts have other effects too, including extra damage when striking from be hind. The array of effects attached to the various arts is broad.
Most notable is the three-item condition chain in Xenoblade Chronicles- Break, Topple, and Incapacitate. These terms will pop up attached to your Arts frequently, and with good reason- they are a form of combat control that your whole party can take advantage of, and all of them can affect.
Break is the key to unlocking Topple. On its own, this status doesn’t actually do anything. While this will make it seem weak at first, remember that your character is part of a party, and the computer runs your allies. The more time your target spends under Break that you inflict, the more chances the computer has to inflict Topple on the target.
Topple is the middle link in the effect chain. A Toppled enemy or character is knocked down and unable to attack or use Arts, stuck on the ground. This is a plenty nice position to put your enemies in, since it stops them from hurting you. Still, they continue paying attention to what’s going on around them, and they will shift their Aggro when attacked- which means that if you can’t kill them while they’re down, you may have just drawn a lot of fire on your more damaging team memebers. However, Topple does unlock Daze.
Daze is the state you want your enemies in as much as you can possibly manage. A Dazed enemy is not only lying on the floor and unable to do anything, but they aren’t even aware- so you can unleash all the damage on them you like without changing their Aggro at all. This not only makes it easy for you to keep the Aggro on your tank character, it makes it easy for the tank to regain Aggro if it was lost before the Daze was set.