"Who one is...is defined by who one isn't."
"To move forward, one must accept these truths."
"Yes, in this prison this cradle
"my dreams and reality became one."
—>An excerpt from "Balduq's Cell"
Ys IX: Monstrum Nox is the ninth primary installment of the Ys franchise, developed and published by Falcom. Originally released on September 26, 2019 in Japan for the PlayStation 4, it is set to release internationally on the same platform on February 2, 2021; the PC and Nintendo Switch versions are due some time in the summer of the same year. Ys IX takes place after Ys SEVEN in "Balduq", a "prison city", located on the Eresian continent northeast of Esteria in the Gllia Eldligen region, with a mystery surrounding the titular "Monstrum", a group of people who possess supernatural powers.
When series protagonist Adol Christin arrives at Balduq along with his traveling companion Dogi, he is apprehended by soldiers of the Romun Empire and thrown into prison for his actions from previous adventures. While escaping from the prison, he encounters a mysterious woman named Aprillis, who proceeds to grant him the ability to transform into a Monstrum. With his newfound identity as the Monstrum "Red King", Adol gets swept up in a plot that involves investigating the unrest behind Balduq and unknown entities behind the "Grimwald Nox".
Continuing the party-based game-play from Ys SEVEN, Ys: Memories of Celceta and Ys VIII: Lacrimosa of Dana, Ys IX features a full three-dimensional world where players are encouraged to explore every nook and cranny of Balduq. Combat remains largely the same with returning mechanics such as "Flash Guard", "Flash Move" and "Break", but the biggest change is the introduction of special Monstrum powers which can be used for combat and exploration, on top of abilities that players already had access to in previous games. As Monstrums are tasked with protecting Balduq from demons called "Larva", players will occasionally participate in Grimwald Nox, which is nearly identical to Beast Raids from Ys VIII with Tower Defense elements. Also, since investigating Balduq is one of the goals of the game, Adol will form a guild and performs various jobs in exchange for information, gaining allies in the process, who serve similar purposes as the castaways from Ys VIII did.
Tropes applicable to Ys IX: Monstrum Nox include:
- Ability Required to Proceed: In each chapter where a monstrum joins your party, it is impossible to go through the story dungeon without using his or her monstrum ability. Later dungeons require uses of multiple abilities to pass.
- Action Girl: Female monstrums, Aprilis, and Iris.
- Alchemy Is Magic: This game reveals that alchemy can be used to create clones of living people, bring memories and thoughts to life, and temper metals in a way that goes beyond simple blacksmithing.
- And Now for Someone Completely Different: Every now and then, the control shifts from Adol and other monstrums to another "Adol", who is still trapped in the prison.
- Anti-Frustration Features:
- The SP now fills up automatically if one does not attack for awhile. As SP costs in skills have generally gone up, this is helpful for those players who struggle with flash guard and flash move and prefer to stay away from enemies.
- Silhouette, one of the associates at the bar, acts as this in regards to general shopping since she will sell the goods from stores throughout Balduq as soon as the player unlocks them. So the player does not have remember which shop sells which.
- Anti-Grinding: In addition to the usual diminishing-returns algorithm Falcom uses on XP, better equipment only become available as you advance into new chapters.
- Broken Bridge: Certain areas of Balduq are unavailable until Adol and his party defeat enough Larva to fill the Nox gauge and overcome Grimwald Nox events, which tend to be Tower Defense mini-games.
- Can't Drop the Hero: Averted like previous games with the party system as Adol does not need to be part of the active party.
- Cardboard Prison: Despite Balduq's infamy as the largest prison in the Romun empire, lots of people escape from it throughout the game.
- Cartography Sidequest: Like the previous two games, Adol is tasked with this and reporting the result to the NPC. Filling the map at 10% intervals will reward players with items or accessories.
- Clark Kenting: After breaking out of Balduq's jail, Adol simply dyes his hair black to avoid drawing attention to himself.
- City of Adventure: Much of the game takes place within Balduq as Adol and other monstrums fight off demons from Grimwald Nox as well as run into various mysterious events that take place there.
- Closed Circle: All monstrums cannot leave Balduq as they are forced to appear whenever Aprilis summons them to battle larva from Grimwald Nox.
- Continuity Nod:
- While interrogating Adol, Ingrid mentions several events that frequently happen to Adol during his adventures, such as his bad luck with boats and tendency to lose all equipment between games, asking Adol if he is doing them on purpose.
- There are several returning monsters from previous games, which Adol can point out in his dialogue options.
- General Leo, one of the characters from Ys: Memories of Celceta, is mentioned to be the one responsible for capturing the city of Balduq during the war between the kingdom of Glia and Romn which occurred eight years ago.
- The gift for Dogi is an apple from Esterior, the setting of the first game where Adol and Dogi met each other for the first time. Similarly, the gift for Jule is a book about the five dragons of Altago, which is central to the plot of Ys Seven.
- Adol, after receiving this game's Infinity +1 Sword, can say something along the line of "One day, this sword will leave me as well...", which alludes to the fact that Adol suffers Bag of Spilling between games.
- In Chapter 8, when Chatelard talks about alchemy, which is central to the main plot of the game, he refers to it as something that Adol encountered in Xandria, the setting of Ys V: Lost Kefin, Kingdom of Sand.
- Conveniently an Orphan: All monstrums except Adol and Doll are this. Justified as they are actually clones of the historical figures from Balduq 500 years ago, meaning they never had real parents to begin with.
- Cloning Blues: The big reveal of the game is that not only is Adol we control for much of the game a clone of the real Adol but also other monstrums except the Doll are clones of the historic figures from Balduq 500 years ago.
- Cute Monster Girl: White Cat and Raging Bull count as this since White Cat is a cat girl and Raging Bull is a literal cow-girl.
- Disappears into Light: All homunculi perish in this manner.
- Fusion Dance: The Crimson King and the real Adol do this near the end of the game as the Crimson King's lifespan is running out and Zora needs to be stopped.
- Gameplay and Story Segregation: Despite being wanted for various reasons, Adol and other monstrums can transform and use monstrum powers right in front of townspeople and guards without any reprecussion during gameplay.
- Giant Spider: There are some aggressive spiders that are several times larger than a human in the game, with bright blue eyes and equally blue spots on their carapace. A particularly large one serves as a boss in Chapter 4.
- Hammerspace: All monstrums and Chatelard simply pull or sheath their respective weapons from nowhere.
- The Heartless: Larva from Grimwald Nox turn out to be these as they are created from negative emotions of people living in the Glia region.
- Impossibly Cool Clothes: The clothes that monstrums wear in general look more like fancy ballroom gowns than practical battle gears.
- Infinity +1 Sword: At the end of the game, the party can find the blueprints for ancient weapons and armors in The Very Definitely Final Dungeon, which Tito can use to craft them.
- "Just Frame" Bonus: Flash Guard and Flash Move from previous games return.
- Legacy Boss Battle: Nygtilger and Vagullion from Ys I: Ancient Ys Vanished - Omen and Ys Origin and Primordials from Ys VIII: Lacrimosa of Dana show up as bosses and regular enemies. Justified in that they are created from Adol's memories.
- The Magic Goes Away: At the end of the game, the destruction of Draupnir's Egg causes the permanent end of Grimwald Nox, which in turn results in monstrums' losing their powers and becoming regular human beings.
- Hybrid Monster: The Bonus Boss, Vaf Medios, is an amalgam of many larva monster types you encounter throughout the game.
- One-Winged Angel: Grandmaster Chatelard and Atola go through this using the power of alchemy.
- Our Homunculi Are Different: They are clones of the living people created through alchemy. Notable in that other homunculi presented in the previous games were tiny Fairy Companions.
- Tomato in the Mirror: It is revealed near the end that Adol we control for much of the game is actually a homunculus created by Big Bad while Adol the player periodically controls for segments of the Balduq prison is the real deal.
- Unexpected Gameplay Change: In the segments where the player controls "Adol" who is still trapped in the prison, the player cannot use any skill, monstrum powers, and double jump and the focus of the gameplay changes to avoiding traps and solving puzzles.
- Was Once a Man: The late-game sidequest reveals that this is the case for Xavier. The chimeras that serve as guardians of The Very Definitely Final Dungeon are this as well.
- Well-Intentioned Extremist: Chatelard wishes to free the region of Glia from the Romun control. Unfortunately, he goes about it by making clones of extraordinary people across the world in order to raise an army. This also applies to Big Bad Zora, who experiments on Adol so he may create a godlike being from Adol's memories in order to bring the threat of Grimwald Nox under control .