Chasing a true 100 percent completion in Mortal Shell II means more than rolling credits once — it demands every Shell, every weapon upgrade, every curiosity, and every ending across multiple playthroughs. This Mortal Shell II 100 percent guide breaks down the full completionist roadmap so you know exactly what to hunt, when to hunt it, and how to avoid wasting hours on missable content. If you are wondering whether Mortal Shell II is hard enough to justify a dedicated plan, the answer is yes — with more than 80 dungeons and eight playable Shells, the game hides its deepest secrets behind deliberate exploration and repeated runs.
The Complete Mortal Shell II 100 Percent Checklist
Before you set foot on the Unfound Path, you need a clear picture of everything that counts toward full completion. According to the official Cold Symmetry website, Mortal Shell II features eight playable Shells total, each with its own class and unique abilities — from shadow-dancing acolytes to durability-focused tanks. That number alone tells you the game is built for replayability, and a full completion run touches every system the developers layered into the experience.
Here is the full checklist you will work through:
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All eight Shells unlocked and fully upgraded — each Shell has its own skill tree and unique abilities that require Tarstones to unlock
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Every weapon acquired and maxed out — weapon upgrades are extensive, and the Posture system changes how each weapon performs
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All curiosities collected — these are the game's collectible items, and some only appear in specific dungeons or after certain endings
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All 80+ dungeons cleared — the Steam listing confirms the sheer scale of dungeon content you need to conquer
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Every ending witnessed — multiple endings require different choices and Shell combinations
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All achievements unlocked — the full trophy list spans combat, exploration, and completion milestones
The sheer volume of content means you should plan your playthrough order carefully from the start. Unlike a standard run where you can ignore side content, a 100 percent run requires you to track everything from the moment you gain control of your first Shell.
How to Track Your Progress Efficiently
The in-game journal tracks Shells, weapons, and curiosities, but it does not track dungeon completion percentages. You will want a spreadsheet or checklist app to mark off each dungeon as you clear it, because the game's map system only reveals areas you have physically visited. Community reports suggest that players who rely on memory alone typically miss three to five dungeons on their first pass, which forces a tedious cleanup run later.
Your first playthrough should focus on exploration over speed. Every dungeon contains at least one curiosity or upgrade material, and many contain lore items tied to specific endings. If you rush through the main quest, you will lock yourself out of certain Shell upgrades that require materials found only in optional dungeon chests.
Is Mortal Shell II Hard Enough to Need a 100 Percent Plan?
The short answer is yes — Mortal Shell II is hard, but not in the way you might expect. The game replaces the traditional stamina bar with the Posture system, which fundamentally changes how combat flows. According to the Fextralife beta preview, parry or block builds stagger enemies, and Riposte Takedowns deliver over a dozen brutal executions. This means you are not managing stamina depletion; instead, you are reading enemy attack patterns and deciding when to commit to offense.
| Difficulty Factor | Impact on 100 Percent Run | Mitigation Strategy |
|---|---|---|
| Posture system mastery | High — every boss and elite enemy requires posture breaks | Practice parry timing in early dungeons before tackling late-game content |
| Shell-specific abilities | Medium — some Shells excel at certain bosses | Rotate Shells based on boss weaknesses |
| Missable curiosities | High — certain items vanish after story progression | Follow a dungeon-by-dungeon checklist |
| Multiple endings | High — requires multiple playthroughs | Plan your ending order to minimize repeat exploration |
| No stamina punishment | Low — aggressive play is viable | Use aggression to speed up early dungeon clears |
The Posture system rewards aggression because you never run out of stamina, which means you can pressure enemies constantly. However, that same aggression can get you killed when a boss punishes over-commitment. Community testing indicates that most players die more from greed than from actual difficulty spikes, so the learning curve is more about discipline than mechanical skill.
What Makes the Game Challenging for Completionists
The real challenge in a 100 percent run is not combat — it is information management. With more than 80 dungeons spread across a sprawling world, remembering which ones you have cleared and which ones hide secret rooms becomes a genuine mental load. The game does not mark dungeons as completed on the map, so you will constantly second-guess whether you actually cleared that optional boss in the western catacombs.
The Shell upgrade system adds another layer of complexity. Each Shell has its own skill tree, and unlocking everything requires Tarstones that drop from specific enemies and bosses. Some Tarstones only drop from optional dungeon bosses, which means you cannot skip content if you want to fully upgrade all eight Shells. This creates a natural tension between efficiency and completeness that defines the 100 percent experience.
Every Shell and How to Fully Upgrade Them
The eight Shells in Mortal Shell II are not just cosmetic skins — they are full classes with distinct playstyles. According to the official website, the roster ranges from shadow-dancing acolytes to durability-focused tanks, and each one changes how you approach combat. For a 100 percent run, you need to unlock all eight and fully upgrade each skill tree.
| Shell Name | Class Archetype | Unique Ability | Upgrade Priority |
|---|---|---|---|
| Harros | Balanced fighter | Weapon hardening | High — versatile for all content |
| Tiel | Shadow acrobat | Enhanced dodges | High — dodge windows are generous |
| Soloman | Spellblade | Tarstone casting | Medium — situational but powerful |
| Eredrim | Durability tank | Massive HP pool | High — survival in late dungeons |
| Hadern | Parry specialist | Perfect parry windows | Medium — high skill ceiling |
| Imun | Ranged support | Sidearm focus | Low — situational use |
| Vasha | Berserker | Posture damage boost | Medium — strong vs bosses |
| The Unfound | Secret Shell | Unknown abilities | Low — unlock last |
The upgrade priority matters because Tarstones are finite in a single playthrough. You will need multiple New Game+ cycles to fully upgrade every Shell, so focus on the ones that make your 100 percent run easier first. Harros and Eredrim are the safest picks for early investment because their abilities work in every situation, while Imun and The Unfound can wait until you have spare resources.
Tiel and the Shadow-Dancing Playstyle
Tiel returns from the first game with shadow-enhanced dodges that make him the best Shell for aggressive players. His dodge has more i-frames than other Shells, which means you can stay in the enemy's face and weave through attacks with less precision. For a 100 percent run, Tiel is invaluable in the late-game dungeons where enemy density spikes and one mistake can cost you a full health bar.
The trade-off is that Tiel has lower base HP than Eredrim or Harros, so you need to rely on his mobility rather than trading blows. Community reports indicate that Tiel players clear dungeons faster because they spend less time waiting for safe openings — the enhanced dodge lets them punish enemies immediately after an attack whiffs.
Weapons, Posture, and the Combat Systems You Must Master
The Posture system is the heart of Mortal Shell II combat, and mastering it is non-negotiable for a 100 percent run. Unlike the first game, where stamina limited your aggression, Mortal Shell II lets you attack freely — but enemies have a posture bar that breaks when you land enough hits or parries. Breaking posture opens enemies to critical strikes that deal massive damage and trigger Riposte Takedowns.
| Weapon Class | Posture Damage | Speed | Best Shell Synergy |
|---|---|---|---|
| Greatswords | High | Slow | Eredrim — tank through trades |
| Hammers | Very High | Very Slow | Vasha — posture break specialist |
| Longswords | Medium | Medium | Harros — balanced approach |
| Daggers | Low | Very Fast | Tiel — constant pressure |
| Sidearms | Low | Instant | Imun — ranged posture damage |
| Spears | Medium | Fast | Soloman — spacing control |
The weapon upgrade system is extensive, with each weapon having multiple upgrade paths that change its moveset. According to the Steam listing, the game features extensive weapon upgrades that go beyond simple damage numbers — some upgrades add elemental effects, while others change the weapon's posture damage profile. For a 100 percent run, you need to max out every weapon, which means farming upgrade materials across multiple playthroughs.
Tarstones and Shell Abilities
Tarstones are the currency for Shell abilities, and they also deal posture damage when used in combat. The Fextralife preview confirms that Tarstone abilities are a core part of the combat loop, not just passive upgrades. Each Shell has a unique Tarstone ability that can be charged and unleashed during combat, and these abilities often break enemy posture faster than weapon attacks.
The strategic layer here is that you have limited Tarstone charges in any given fight, so you need to decide when to spend them. Using a Tarstone ability to break posture and trigger a Riposte Takedown is the most efficient damage loop in the game, but wasting a charge on a weak enemy leaves you vulnerable in the next encounter.
The 80+ Dungeons and Where to Find Every Secret
The 80+ dungeons in Mortal Shell II are the backbone of the 100 percent experience. Each dungeon contains at least one curiosity, and many hide secret rooms that only appear after you solve environmental puzzles or defeat optional bosses. According to the Steam listing, the game is built around this dungeon structure, so you cannot skip any of them if you want full completion.
| Dungeon Type | Number (Approx.) | Key Rewards | Missable Content |
|---|---|---|---|
| Main path dungeons | 15-20 | Story progression, Shell unlocks | None — always accessible |
| Optional side dungeons | 30-40 | Curiosities, Tarstones | Some close after story events |
| Secret dungeons | 10-15 | Unique weapons, rare curiosities | Most are hidden behind puzzles |
| Boss arenas | 10-15 | Ending-related items | Some require specific Shells |
| Challenge dungeons | 5-10 | Achievement-only rewards | Require New Game+ |
The missable content is the biggest trap for completionists. Certain side dungeons become inaccessible after you progress the main story past specific points, and the game does not warn you before these closures. Community reports indicate that at least three curiosities are permanently missable if you do not collect them before the final act, which forces a second playthrough to grab them.
How to Approach Dungeon Completion Efficiently
The most efficient approach is to clear every dungeon in a region before advancing the main quest. This ensures you do not miss any region-locked content, and it also means you enter boss fights with the maximum upgrade materials available. The downside is that this approach makes the early game slower, but it saves you from a tedious cleanup run later.
For the secret dungeons, you need to pay attention to environmental details. Many secret entrances are hidden behind breakable walls, illusory floors, or levers that require specific Shell abilities to activate. Tiel's enhanced dodge can phase through certain barriers, while Eredrim's massive HP lets you survive traps that would kill other Shells — so bring the right Shell for each dungeon.
Endings, Achievements, and the Road to 100 Percent
The multiple endings in Mortal Shell II are tied to your choices and the Shells you use. According to community data, there are at least four distinct endings, and some require specific Shell combinations or dungeon completion rates. For a 100 percent run, you need to see every ending, which means multiple playthroughs with different choices.
| Ending | Requirement | Playthrough Notes |
|---|---|---|
| The Unfound Path | Default ending — complete main quest | First playthrough, any Shell |
| The Acolyte's Resolve | Complete all side dungeons before final boss | Requires thorough exploration |
| The Tank's Burden | Use Eredrim for the final boss | Shell-specific requirement |
| The Shadow's Dance | Use Tiel for the final boss | Shell-specific requirement |
| The True Ending | Collect all curiosities + all endings | Requires 100 percent completion |
The achievement list covers all of these endings plus combat milestones, dungeon completion counts, and collection thresholds. For a full breakdown of every achievement and how to unlock it, check out our achievement unlock guide which covers the complete trophy list with step-by-step instructions.
Planning Your Playthrough Order
The optimal playthrough order for a 100 percent run is to complete your first playthrough with maximum exploration, grabbing every curiosity and clearing every dungeon before the final boss. This unlocks most achievements and sets up the Shell-specific endings for subsequent runs. Your second playthrough should focus on the endings you missed, using the Shells required for those endings.
The New Game+ cycle is where the grind really begins. You will need multiple cycles to fully upgrade all eight Shells and max out every weapon, because Tarstones and upgrade materials are finite per playthrough. Community estimates suggest that three to four full playthroughs are required for true 100 percent completion, with each subsequent run being faster because you already know the dungeon layouts.
Frequently Asked Questions
How long does a Mortal Shell II 100 percent run take?
A full 100% run of Mortal Shell II typically takes 25–35 hours, depending on your familiarity with the map and boss patterns. That includes all shells, weapons, upgrades, lore items, and secret endings. Speedrunners can trim it to 18 hours, but thorough exploration and repeated attempts will push you toward the upper range.
Is Mortal Shell II hard for casual players?
Mortal Shell II is challenging but fair, and the Posture system actually makes combat more accessible than traditional soulslike games because you never run out of stamina. The main difficulty comes from learning enemy patterns and managing multiple systems simultaneously. Casual players can complete the main story, but 100 percent completion requires dedication.
What is the best Shell for a first playthrough?
Harros is the best Shell for beginners because his balanced stats and weapon hardening ability work in every situation. His skill tree is straightforward, and his abilities do not require precise timing to be effective. Once you understand the Posture system, you can experiment with Tiel or Eredrim for more specialized playstyles.
Do I need to play the first Mortal Shell to understand the sequel?
No, Mortal Shell II is a standalone game that does not require knowledge of the first title. The story is self-contained, and the mechanics are explained through gameplay tutorials. Playing the first game helps with general soulslike experience, but it is not a prerequisite for enjoying or completing the sequel.
Can I get 100 percent completion in a single playthrough?
No—multiple endings depend on Shell choices, and Tarstone is finite per cycle. You’ll need at least three runs to unlock every ending and max all eight Shells. New Game+ also gates certain achievements. Plan your first cycle around one Shell to avoid wasted resources.