Characters & Enemies
Meet the inhabitants of The Vessel
Protagonist
MIO
The main character of MIO: Memories in Orbit. A mysterious entity navigating The Vessel, equipped with hair tendrils that function as a grappling hook and various combat abilities.
Abilities
Hairpin Grapple, Glide/Sail, Wall Climb/Striders, Dodge, Slingshot Punch, and various combat abilities. Can equip modifiers to customize playstyle.
NPCs
RAD
Early game guide NPC located in Dwellings. Provides helpful tips and sells the Analyser modifier.
Shii
NPC in Severed Spine who provides map unlock and fast travel functionality. Requires Nacre donations.
Mel
NPC that can be rescued in Nexus area. Saving Mel allows purchase of the Gratitude modifier for 1 Nacre Droplet.
Enemy Types
Security Drone
Horizontal patrol pattern, fires single projectile when MIO in range.
Single energy shot with predictable timing
Jump over projectile, aerial attack from above
Predictable pattern, long attack cooldown
Repair Bot
Ground-based movement, attempts melee repair tool swing.
Short-range tool swing
Maintain distance, use ranged attacks or quick melee hit-and-run
Slow movement, no ranged capability
Mechanical Bird
Aerial patrols, dive bomb attacks.
Diving strike followed by flying projectiles
Time attacks during dive, attack at apex before strike
Vulnerable during dive animation, predictable flight path
Furnace Unit
Slow movement, heat-based attacks.
Flame breath, molten projectiles, overheating explosion
Stay at mid-range, dodge flame breath (telegraphed), retreat during overheating phase
Slow movement, long attack animations, vulnerable after explosion
Elite Combat Unit
Maximum aggression, advanced combat AI.
Full combo chains, feint attacks, perfect dodges
Treat as boss-lite, learn full moveset, use dodge to match their dodges
Combo commitment, vulnerable after combo finish
Boss Encounters
Egis - Worn Out Sentinel
The first mandatory boss encounter. A worn-out sentinel that guards the path forward.
Strategy
Stay above Egis; watch for his dash attack when he "revs up" like a runner. Jump immediately when he reappears. Nacre Basin available above arena behind icy gate for healing.
- First boss might surprise you - ensure full health before entering
- Watch for the "rev up" animation before dash attacks
- Use the Nacre Basin above the arena for healing
Crow - Automated Reaper
An automated reaper found in the upper areas of Feral Undergrowth.
Strategy
Attack when Crow lands (easiest damage window). Keep attacking during spinning animation (no damage). Maintain distance during aerial phase; focus on dodging projectiles. Phase 2 increases speed but uses same patterns.
- Patience is key - don't rush the aerial phases
- Focus on dodging during aerial phase
- Phase 2 is faster but uses same patterns
Flora - Sentient Pearltrap
A sentient pearltrap that guards access to the Aviaries. Essential for progression.
Strategy
Watch for vine raises at back of screen and screeching sound for poison attacks. Stay left side of screen for most vine attacks; be prepared to jump. One-gap poison rain requires precise positioning or dodge.
- Essential boss for progression; unlocks Dodge ability access
- Listen for screeching sound before poison attacks
- One-gap poison rain requires precise positioning
ACAT - Nacre Engraver
An optional challenge boss in Dwellings. Much tougher than early mandatory bosses.
Strategy
Bait attacks by moving side-to-side; damage during ground phase. Jump during most attack preparations except aerial attacks (stay grounded then jump when he strikes). Conserve double jump for extended air time.
- Much tougher than early mandatory bosses
- Dodge ability strongly recommended
- Conserve double jump for extended air time
Calderon - Unyielding Furnace
An unyielding furnace boss in Foundations. Similar to Hollow Knight: Silksong's Fourth Chorus.
Strategy
Attack moving head while watching four mechanical claws. Red glow = about to strike. High claws = ground pound (stay high). Side claws = middle swing (avoid center).
- Keep eyes on claws while attacking head
- Red glow indicates incoming strike
- High claws = ground pound, stay high
Atmos - Weather Control Unit
A weather control unit boss in Foundations. Requires Sail ability for optimal strategy.
Strategy
Maximum damage during snowman phase. Stay close after transformation, jumping over attacks. Critical: Use Sail to avoid rapid-fire ice bullets when Atmos moves to screen edge (can't jump over these).
- Don't waste snowman phase - deal heavy damage immediately
- Use Sail to avoid rapid-fire ice bullets
- Stay close after transformation
Nabuu - Keeper of the Breath
Keeper of the Breath and major story boss. Rewards The Breath pearl fragment.
Strategy
Ground phase - stay underneath, attack chest (avoids most attacks). Back-of-screen phase - use purple flowers to stay airborne, Sail between attacks to avoid rising flood and falling explosives. Watch for horn channeling (white glowing strands warn of ground/side attacks).
- Most complex boss so far - three distinct phases
- Use purple flowers to stay airborne
- Watch for white glowing strands before attacks
SAWLONG
Not a traditional fight - escape sequence like Crash Bandicoot boulder chase.
Strategy
Not a traditional fight - escape sequence. Use all abilities; memorize route if caught. Focus on reaction time and constant forward movement.
- Appears twice in full playthrough
- Memorize the route
- Use all abilities for mobility
Anra & Dr Halyn - Anti-Rat Weapon
Two-phase boss fight in Lab. Phase 1 is Anra, Phase 2 is Dr Halyn.
Strategy
Phase 1 (Anra) - stay close to avoid projectiles; use dodge for melee attacks. Between phases, destroy yellow orb in mechanical hand to break shield. Phase 2 (Dr Halyn) - easier than Phase 1; avoid arm's ground pounds while damaging Anra's corpse in hand.
- Difficulty front-loaded; Phase 2 is relief
- Destroy yellow orb between phases
- Stay close during Phase 1
Friends
Wall-climbing boss fight in Metropolis. Unique combat mechanics.
Strategy
Stay close to blob, deal constant damage. Attack gooey extremities to remove screen coverage. Coordination challenge from climbing during combat.
- Practice wall-climb combat controls first
- Attack gooey extremities to clear screen
- Stay close for constant damage
Lombre - Intrusive Fertiliser
A pattern recognition boss with dig-through-ground mechanics.
Strategy
Classic dig-through-ground pattern. Watch visual cues for emergence point; avoid then damage when stopped. Dodge side leaps; damage when he hits opposite wall. Mid-fight poison rain has one safe gap - dodge as backup.
- Pattern recognition boss
- Watch for visual cues
- One safe gap in poison rain
Vlad
A boss in the mysterious Redacted area. Requires 360-degree awareness.
Strategy
Attack center body while monitoring circular arena edges. Wall vibration = incoming spin; jump to avoid spikes. Don't attack during spin phase - focus on survival. Electrical current adds complexity in later phases.
- 360-degree awareness required
- Wall vibration indicates incoming spin
- Don't attack during spin phase
Ancile and Targa
Two Egis-style enemies. High tempo, low complexity.
Strategy
Two Egis-style enemies. Focus one when together (move in unison). Relentless when separate - constant movement. Easier than difficulty suggests if you beat Egis easily.
- High tempo, low complexity
- Focus one when together
- Constant movement when separate
Debby
Platforming + combat hybrid boss with disappearing floor mechanics.
Strategy
Explosives destroy ground beneath you - watch footing. Use double jump for large gaps. Rapid-fire attack from edge is damage opportunity - land on Debby during this move for constant hits.
- Platforming + combat hybrid
- Watch footing constantly
- Land on Debby during rapid-fire for damage
Poltergates
A two-phase boss fight. Community favorite aesthetically.
Strategy
Phase 1 - defeat released standard enemies. Phase 2 - manifests duplicate; both move independently but simultaneously. Watch for aerial drop attack from one while tracking second.
- Community favorite aesthetically
- Watch for aerial drop attacks
- Both move independently in Phase 2
Sol and Vin
Late-game skill check boss. Can also be fought in The Vaults.
Strategy
Early fight - ground shrinks to center circle, combine jumping and dodging. Predictable pattern: one swings while other slams. Final phase - ground disappears completely; use Hairpin to stay airborne. Take final phase slowly, attack only when safe.
- Late-game skill check
- Use Hairpin to stay airborne in final phase
- Take final phase slowly
The Keeper of the Heart
The final boss of the game. Highest HP of any boss - endurance fight.
Strategy
Highest HP of any boss - endurance fight. Combination of jab, projectile, and slam attacks from previous bosses. Take time to learn patterns. Minimize damage taken over rushing offense. Best damage windows after slam attacks (longer ground time).
- Marathon not sprint - patience wins
- Equip Protective Overlay modifier + max coating upgrades
- Best damage windows after slam attacks
True Ending Boss
True ending boss. Requires all four Pearl fragments.
Strategy
Spoiler content - complete True Ending path to unlock.
- Requires all four Pearl fragments
- Equip all fragments before final boss
Secret Ending Boss
Secret ending boss. Post-credits content.
Strategy
Spoiler content - complete Secret Ending path to unlock.
- Requires all 12 Candles
- Complete True Ending first
Boss Information In Progress
General Boss Tips
Learn Patterns
Most bosses have predictable attack patterns. Observe and learn before committing to attacks.
Use Abilities
Dodge, Glide, and Wall Climb are essential for many boss encounters. Master your movement.
Modifier Setup
Equip modifiers that complement your playstyle. Protective Overlay is recommended for difficult fights.
Healing Opportunities
Many boss arenas have Nacre Basins or safe zones. Use them strategically during fights.