The Hidden One is one of four bosses of the Double Reed Tower of Sand that are palette swaps of enemies previously encountered in Eternal Sonata. In this case, it is a palette swap of the Killer Knight.
The Hidden One's normal physical attack is a whack with its sword. It mainly relies on a strong roster of Special Attacks, all of which carry a chance of knockdown. Violet Death is four slashes with the sword on all in range with a powerful finishing blow.Red Swirl is three hits on all in range from a slight distance. Furrow is three lashes with its tail on a target and anyone else close by from behind. Finally, Heavy Stomp is a strong foot stomp on targets standing very close by, though if the target is positioned correctly, then this attack will simply miss entirely.
The Killer Knight was back in Chapter 2 in Fort Fermata, but if the player can remember the pattern of its attacks, then that will be an advantage in this fight, as Hidden One's attacks are essentially the same, just more powerful. This boss possibly has the most powerful attacks of all of the bosses in the Double Reed Tower, but it is slow and its attacks are generally very easy to Guard against, or even Counterattack. It also has relatively low HP.
Bring in a Very Odd Chocolate item to decrease its attack power and a Sock Incense to decrease its defense. Fill the rest of the Item Set with Angel Trumpets and Goddess Bouquets, and perhaps one or two Clover items. Having March inflict Slow can further debilitate this already lumbering boss and its such a large target that Viola can easily do a lot of damage with arrows. The only major thing to watch out for is that it is likely to sometimes get two turns in a row.
In Encore Mode, watch out for the powerful punch of its attacks and be wary of the fact that it will get two turns in a row even more often. Build a full set of Harmony Chains prior to starting the battle and use at least one distance attacker to keep it from being able to gang up on all three characters at once.
- In the PlayStation 3 version of Eternal Sonata, this boss's HP was reduced by around 30000 points, and the EXP granted for defeating it was decreased by nearly 2/3.
- In the Xbox 360 version, following the battle, a scene is presented in which, against a black background, Frederic asks what lies at the end of the journey. Salsa says she sure the road leads somewhere and March replies that Frederic is speaking of something of a more spiritual nature. Salsa says he's talking like he's going to die soon and Viola admits that she can't see where she's going either, but it's surrounded by light. Salsa says that if it's a choice between not being able to see because it's too bright or too dark, then the first option is better. In the PlayStation 3 release, a scene instead takes place in which Viola tells Frederic and Polka that their droopy faces are bringing down morale and that Allegretto won't be able to fight seeing Polka like that. She then asks Frederic what makes him have such a gloomy expression and Frederic says that he was thinking about what would happen once the dream comes to an end. Viola tells him that when a dream ends you just open your eyes to a new day and that since he's a composer, he could even set his dream to music.