Zzx Ru

The ultimate Antibody and the final line of defense of the Planet's Consensus of Wills, this monstrosity attacks the party upon them trying to contact the Wills of Ar Ciel to persuade them into accepting the Heart of the Land they brought to the Planetary Core. However, Zzx_Ru grabs the Heart and begins trying to destroy it, which is why you will be fighting it. This monster is the first phase of the final battle, and it has XaaaCi as its background music. Its name translates from Carmena Foreluna and Hymmnos to "The Will that Protects the Gods".

Zzx_Ru has the following attacks: launching energy balls aimed to where your Vanguards are standing at the moment, summoning Eggs, and finally its Stored Attack, which makes it a great danger: Attacking the Heart of the Land. As its name says, it will grab the Heart, which is still floating in the battlefield, and begin trying to crush it. This will gradually weaken the Heart's shell, and if it manages to use it four times, the Heart will shatter and you will get a Game Over regardless of the status of your party. However, it isn't much trouble to interrupt it from using it as long as you pay attention to it. On the other hand, Zzx_Ru has just average resistances and stats for this point in the game, and its large size and inability to move make it easy for all your Vanguards to attack it at the same time.

So the best you can do is keep attacking, making sure to take advantage of the large number of red waves that appear right at the start of the battle, and kill the Eggs as soon as they are summoned, as their Suicide Bomber attack can instantly kill your Reyvateil if they manage to get to her, not to mention gravely injure your party members. Once you're ready, launch a Flipsphere and that should be more than enough to defeat it. However, make sure to not use up all your healing items, as you will have a much longer battle after this.