- Before you squats an abomination born from your most terrible nightmares. The monster dwelling in those blood soaked depths must be the labyrinth's final enemy! Unsheathing your weapons, you prepare to face the heart of the labyrinth!
- —Yggdrasil Core introduction, Etrian Odyssey
Yggdrasil Core.
Yggdrasil Core (フォレスト・セル Forest Cell in Japan, and Primevil in the first installment) is the true final boss of the first Etrian Odyssey game and its remake.
It can found in the B30F (The sentinel of eternity), the final floor of the Claret Hollows, and is the hardest boss in both games it appears in. It is by far one of the most powerful entities in the entire series.
This abomination is the sentient Yggdrasil Tree's core, the last stand of the labyrinth. It has many forms of attacks, having control over the three elements to cast devastating, lost spells, or using its long tentacles to rip apart unlucky explorers. Should one survive those attacks, it can devastate its enemies in other ways too, using hallucinating pollen to destroy the mind, or using its powerful magic to rot its victims alive, leaving nothing in its wake.
History[]
Primevil as seen in the ending movie of Untold
In Etrian Odyssey, very little was revealed about Primevil. The only known fact, revealed by the Bestiary Entry (or Monstrous Codex), was that Primevil is the heart of the Yggdrasil Tree.
In Story Mode of Etrian Odyssey Untold, its backstory is expanded and elaborated upon. Renamed as the Yggdrasil Core, Primevil is confirmed to be the main part of one of the seven mighty trees, created during the Yggdrasil Project, a project in which scientists had tried to create something meant to purify the world, absorbing all the pollution so that mankind could live properly again. The trees managed to succeed in their original task. However, due to the enormous amount of pollution absorbed by it, their cores would eventually mutate and become unstoppable monsters. They had hypothesized this, and thus Frederica Irving offered to be shut inside a capsule that would awaken her exactly one thousand years later.
In the meantime, various other failsafes were prepared - Gungnir units, which are designed to destroy the Core at the cost of literally everything in its vicinity. The town of Gotham was subject to one such unit and was thoroughly annihilated. M.I.K.E., the AI overseeing Etria's Gungnir unit, was hellbent on activating the Gungnir, and turned against the party when they suggested an alternative means of destroying the Core without sacrificing Etria. The party eventually obtains the Yggdra Virus, a special countermeasure developed by Visil as a last-ditch effort to weaken the Core enough for them to defeat it.
Primevil (Etrian Odyssey)[]
| Primevil | |
| |
| Description | |
|---|---|
| The Labyrinth's core which erected the Claret Hollows to protect itself. | |
| Enemy Data | |
| HP | 90000 |
| ATK | 585 |
| DEF | 170 |
| EXP | 0 |
| Skills | Cyclone Slash Rush |
| Items | Demon Core |
| Weakness |      
|
| Resistance | None |
| Status Resistance | 
|
| Status Immune |            
|
Primevil is the ultimate final boss of Etrian Odyssey. Not much has been revealed about it; in fact, the only known detail is that Primevil is the core of the great Yggdrasil Tree. Before you can fight it, however, you must have killed the Wyrm once; the beast has a seal on the door that leads you closer to Primevil, which can be unlocked once you defeat it.
Although unnecessary, it is recommended that you also defeat the Dragon and the Drake, as one has sealed a door leading to a healing fountain and the other has sealed a warp area, which would allow you to travel freely from the Stratum entrance to B30F.
Once you step through the Wyrm's unlocked door, you will have to face weaker clones of the three elemental dragons; Drakoid, Dragoid and Wyrmoid in the aforementioned order. You cannot head back once you enter, with the exception of using a Warp Wire.
You may finally battle Primevil after defeating the three clones.
Skills[]
- Explode (Uses None): Deals overkill, fire based damage to the party.
- Frigid (Uses None): Deals overkill, ice based damage to the party.
- Storm (Uses None): Deals overkill, thunder based damage to the party.
- Wall (Uses None): Bugged, never used. Intended effect was to nullify physical damage to Primevil, and counter-attack with overkill untyped damage to the attacker.
- Membrane (Uses None): Nullifies elemental damage to Primevil. Counter-attacks with overkill untyped damage to the attacker.
- HP Up (Uses None): Strangely, this attack does nothing, skipping a turn.
- Necrosis(Uses Head): Instant death attack on the whole party. Almost guaranteed to work. Very dangerous, can easily cause a instant Game Over if your party lacks death resistance.
- Entangle (Uses Legs): Binds all body parts of the whole party, almost guaranteed success rate. Extremely dangerous if your buffs are about to vanish, rendering you defenseless against the boss' powerful attacks.
- Pollen (Uses Head): Inflicts random status ailments to the whole party.
- Smash (Uses Legs): Deals heavy crush based damage to the whole party.
- Slash (Uses Arms): Deals very heavy, slash based damage to one target. Hits four times in a row. Very powerful, may kill even with defense buffs.
- Rush (Uses Arms): Deals heavy, pierce based damage to random targets. Hits up to 6 times in a row.
- Resolve (Uses Head): Remove the buffs of the whole party. Used if your party has at least 10 buffs. Very slow.
Drops[]
- Demon Core (Worth: 18000 en)
Conditional Drop[]
- None
Yggdrasil Core (Etrian Odyssey Untold)[]
| Yggdrasil Core | |
| |
| Description | |
|---|---|
| The Labyrinth's core, which erected the Claret Hollows to protect itself. | |
| Enemy Data | |
| HP | 90000 |
| ATK | 99 |
| DEF | 75 |
| EXP | 999999 |
| Skills | Land Slash Activate Armageddon |
| Items | Demon Core True Demon Core 
|
| Weakness |   
|
| Resistance | None |
| Status Resistance |       
|
| Status Immune |     
|
The Yggdrasil Core is the final boss of Etrian Odyssey Untold. It is the main antagonist and final boss of Story mode, and the Classic mode superboss. In the main story, the player warps near its lair straight from B25F. The version fought as the final boss in the Story Mode is way weaker than the original core, due to a powerful composite used by the party to weaken it. In order to fight the Core at its full strength, you need to venture through to B30F of the Claret Hollows the long way after finishing the game. In Story Mode, the party can rematch the full-power Yggdrasil Core as many times as they want, while in Classic Mode the Yggdrasil Core respawns every 14 days like other on-field bosses.
When the party finally reaches the creature's lair, using the final geomagnetic pole, the Highlander uses the Yggdra Virus, given to them by Visil, on Yggdrasil Core, in order to greatly weaken it. Eventually, they manage to defeat it. Not long after that, however, the monster rises again, with its full power back. Kupala comes to the scene, revealing that her folk's original purpose was to help in destroying the core, and sacrifices herself, giving the Highlander's spear tremendous power; enough to defeat the beast. After a fierce battle, the party succeeds in defeating the mighty creature, bringing an end to its terror.
Skills[]
- Explode (Uses None): Powerful ranged fire attack to entire party
- Freezing (Uses None): Powerful ranged ice attack to entire party
- Thunderstorm (Uses None): Powerful ranged volt attack to entire party
- Demonic Rush (Uses Arms): 3-6 strong melee stab attacks across random targets
- Land Slash (Uses Arms): 4 strong cut attacks to a party member
- Root Cyclone (Uses Legs): Powerful ranged bash damage to entire party
- Activate (Uses Head): Increases ailment chance for 5 turns
- Necrosis (Uses Head): May instantly kill entire party
- Ancient Pollen (Uses Head): May inflict random ailments on entire party
- Entangling Ray (Uses Legs): May inflict random binds on entire party
- Cell Membrane (Uses Arms): Blocks all attacks on this turn and launches a powerful counter-attack against the whole party for every attack used against it.
- King's Resolve (Uses Head): Removes all of the party buffs. Used at random points of the fight if your party has a large amount of buffs. The boss will always use Armageddon on the next turn.
- Armageddon (Uses Head): Incredibly powerful ranged non-elemental attack to entire party. Nearly impossible to survive via normal means, as it easily inflicts over 2000 damage.
- Segment (Uses None): Recovers a massive amount of health and moves into next attack phase
Drops[]
- Demon Core (Worth: 35000 en)
- Unlocks the Ameno-Habakiri (255 ATK, +80 HP), one of the best katanas in the game.
- This item can only be obtained at the end of Story Mode.
- True Demon Core (Worth: 1000000 en)
Conditional Drop[]
- The Yggdrasil Core's conditional drop has a unique condition. In order to get the True Demon Core, you must defeat the boss at its full strength, in the postgame. You cannot obtain this item when fighting the Core at the end of Story Mode, not even with the assistance of a Formaldehyde. The drop unlocks nothing, only selling for 1,000,000en and making up the final entry in the Item Compendium.
Strategy[]
- See Yggdrasil Core/Strategy for more information.
Trivia[]
- Although Primevil has no back-story in Etrian Odyssey, it was given one which its remake, Etrian Odyssey Untold's plot, revolved around. If you compare Yggdrasil Core's (Primevil renamed in the remake) back-story with Etrian Odyssey IV's final boss, the Heavenbringer, both histories are in a way very similar. This fact gives a possible hint that both EO1/EOU and EO4 takes place in the same universe, which is later confirmed in Etrian Odyssey 2 Untold, which establishes that all games take place in the same world.
- Primevil's battle theme in Untold, With Much At Stake, is a remix of a song called The Battlefield that Never Sleeps, found in the first Etrian Odyssey's soundtrack, but was never used for unknown reasons. The FM version of the song is the same as the original.