The party travels through the maze-like passages of Fort Fermata and eventually reaches the exit. Before they can use it, however, they must first face the Killer Knight, which drops a key that also unlock other doors in the fort.
The Killer Knight's normal physical attack is a slash with one of its swords and a slash with the other. It also possesses four different Special Attacks. Its White Swirl is a three-hit attack from a slight distance and it can hit multiple targets if they are grouped very closely together. Plow is three lashes with its tail that can also hit targets standing behind or to the side of it. Stomp is one hit on a single character with a chance of knockdown. Finally, its most devastating Special Attack is Red Death, four slashes with its swords that can hit multiple targets and again cause knockdown.
The biggest challenge related to Killer Knight isn't its attacks, but rather its massive HP total, which is far higher than any other opponent the party has come across so far. Begin by taking out the Maledictors, which can definitely present a threat if not quickly dealt with. Thankfully, these carry the HP of normal Maledictors rather than the boss Maledictors fought on the Chorus Plains, so they should fall quickly. After that, go for the Killer Knight. A good trick is to try to position your melee attackers directly underneath the Killer Knight. If positioned correctly, then when it uses Stomp, the attack will miss completely. If you need to heal, then have your characters move away somewhat from the Killer Knight. Another good trick is to keep it moving, as it doesn't have any attacks it can use from a great distance, and so must close in order to use its attacks, taking up time. Positioned correctly, Viola can cause strong damage from a distance, and is even more valuable in wearing down this boss's high HP total in the PlayStation 3 version, in which her distance attacks hit for greater damage. Allegretto, Frederic and Beat can all build up a large amount of Echoes and then unleash powerful Special Attacks. Polka is probably not the best choice for this battle, as she can't use her healing skill three times in one turn like Frederic can, unless already standing in the light. She doesn't learn her Earth Heal until Level 16. While Viola gains her Heal Arrow spell that heals all characters at Level 15, you really only need to be around Level 12 in order to win this battle with the right tactics. Most of its attacks are fairly easy to Guard against and none of them can KO your characters unless their HP is already in yellow or red.
In Encore Mode, the best party is Allegretto, Frederic and Viola. Either Allegretto or Frederic can unleash a Special Attack once Echoes are at 24 or 32 and then begin a Harmony Chain with a total of five different special attacks used for massive damage and possibly even some healing if Frederic is standing in the light. If you've acquired some Odd Chocolates from the monsters in the dungeon, try adding one or two to the item set to lower Killer Knight's attack power. Otherwise, just load the massive item set with Angel Trumpets and Club Clovers, which you probably won't even need too many of.
- If playing in Normal Mode, the Party Level is increased to 3 after Killer Knight is defeated.