Chain Attack (XC1)

Chain Attacks are a major battle mechanic in Xenoblade Chronicles. By consuming the entire, the player can select a series of attacks for each party member to perform in rapid succession.

Overview
When the party has a full of all three blocks, the player can initiate a chain attack, which instantly spends all three blocks and commands all party members to run up to the enemy the player has targetted. The player selects a for the party leader to use, followed by one for the second party member, and then another for the third. From here, the player must succeed at a chain link action command for control to loop back around to the first party member, and for every additional art afterward. Up to 15 extra links can be done per chain attack, so a chain attack can consist of between 3 and 18 arts fired in rapid succession. Arts may be selected even if they are currently on cooldown, but only talent arts can be selected more than once per chain attack.

When a chain attack is activated, all party members immediately stop what they're doing, even if the art they're executing hasn't done anything yet. Some care should be taken to avoid interrupting arts in this way, as their cooldown is still spent. By contrast, enemies will continue their current art if they have passed the windup phase, and the chain attack will not begin until they are done. This means party members can still take damage after the chain attack is fired but before it begins. However, once a chain attack is triggered, party members are immune to any status or debuff that would prevent them from participating (e.g. ), and they will survive any lethal attack with 1 HP. This resilience continues for the entire duration of the chain attack. As a result, it is possible to save party members from otherwise certain death by activating a chain attack.

While a chain attack is in progress, time is stopped on the battlefield; characters and enemies animate for the attacks made and taken, but debuff timers are halted and damage-over-time effects do not activate. For example, it does not matter if an enemy is toppled for 3 seconds with the first art of a chain attack or the last, the 3 seconds does not begin until the chain attack ends; yet the enemy still is toppled and suffers all the effects of it, even if the timer is not yet decreasing. This makes chain attacks ideal for scoring the bonus effects of arts that are normally slow enough to execute that they don't hit until after it's too late.

Enemies' resistance to is bypassed during chain attacks, making them the only practical way to break and topple certain foes. Immunity to break is not bypassed, nor are any other resistances.

Enemies may unexpectedly change their aggro target as a chain attack begins, but once it is in progress, they cannot act on any further changes until it's over. Party members cannot move to take advantage of positioning once the chain attack is used, so it's important to be wary of this.

If a party member is d, d, asleep, confused, or under Arts Seal, they cannot participate in a chain attack. This is also the case for certain arts such as or. If someone in the party cannot participate, the chain attack will continue with only two members, with the chain links beginning after the second art. A chain attack cannot be activated if the player character cannot participate, or if both other party members cannot.

Killing an enemy during a chain attack grants a full bar of party gauge, +25% EXP, +25% AP, and +100% SP. (This is also the case for enemies that are not the chain attack's target.) The party will then target the nearest enemy and continue the chain attack.

If a party member cannot get into melee range of the targetted enemy for any reason (obstacles, bad pathing, deep water) after a time limit, they will stop trying and stay as far as they got. They will only be able to select arts that can reach the targetted enemy, or arts that can target themselves or allies within range. If no arts are available for this reason, the character's turn is skipped. If the entire party is unable to do anything, the chain attack ends prematurely.

Chain multiplier
Using arts of the same colour in succession during a chain attack adds to their arts multiplier, increasing the damage or healing they do. Not all arts have an effect that can be chained in this way, but they still count towards the colour chain. Talent arts are wildcards, maintaining the colour chain regardless of what is used before and after.

Chain links
The ability for the chain attack to loop back to the first party member, and every step after that, is mostly random with some controllable inputs. The chance that a link is available is: tension + 30*(affinity/5000) + skills + command
 * tension is the tension of the party member that just used their art as a number. As a result, having good tension is up to a +10% bonus, while bad tension is up to a -20% penalty.
 * affinity is the affinity between the current party member and the next party member. As a result, familiar party members will have up to a +30% bonus, while new party members will have no bonus at all.
 * skills are bonuses provided by the Chain of Friendship and Ties of Friendship skills. If both are active via skill links, the total bonus is +20%.
 * command is 20 if the previous action command was a "perfect" rather than a "success". Otherwise, it is 0.

If all these bonuses are combined at maximum potential, the total chance of a chain link reaches 100%, thus guaranteeing one. However, this is difficult to achieve, as it requires very high tension, maximum affinity, and multiple skill links. In addition, as there is no "previous action command" for the first skill link, it cannot be higher than 80%. Therefore, it is impossible to guarantee that a chain attack will continue past the first three arts.

Of course, this is only the chance that the button prompt will appear. If the player misses, the chain will come to an end regardless. The speed and thus difficulty of the action command increases for each link.

Strategy
There are many ways to best utilize chain attacks.
 * Topple hardy foes - Many enemies beyond early-game resist break. Chain attacks are an easy way to get around this and topple them anyway, which is especially important versus Mechon or enemies with s.
 * Massive damage - Simply using many red (physical) or purple (ether) arts in succession will stack up a large chain multiplier and thus do huge amounts of raw damage. This requires the party to share many of the same class of art.
 * Evade cooldowns - Arts can be used in chain attacks even if on cooldown, which lets them be used much more often than otherwise possible. Examples include using a daze art in a chain attack and using it immediately again afterward to double the duration, using a power move such as Sword Drive and then launching a chain attack to use it again right away, or restarting an aura that would otherwise take a while to recharge.
 * Delay visions - s, like other things, do not count down while a chain atttack is in progress. Using a chain attack to deal with them affords a lot more leeway.
 * Survival - It is often somewhat overkill to colour-chain healing arts, but it can make a difference in dire situations. Simply triggering a chain attack to survive huge enemy arts can also be more efficient than spending the party gauge on revivals instead.

Of most note is the ability to "pivot" chain attacks from one strategy to another via using the wildcard aspect of talent arts to maintain the colour multiplier. It is difficult to ensure that AI party members will have their talent arts ready to do this with, so if the player wishes to do so, they will have to pay close attention to the corresponding voice lines to know when they are ready. Barring exceptional circumstances, is the only character who can practically use their talent art more than once per chain attack, allowing her to pivot multiple times for complex strategies.

Enemy chain attacks
Certain groups of enemies can initiate chain attacks. During this time, the player is unable to do anything as the group of enemies launches arts in succession. Enemy chain attacks do not wrap around; each enemy always gets a single turn.