Creatures and Enemies

Crimsonland features 6 base creature types with hundreds of variants created through tint, size, and stat modifications. Understanding creature behavior and spawn patterns is essential for survival.

Creature Types

From src/crimson/creatures/spawn_ids.py:12-19:

class CreatureTypeId(IntEnum):
    ZOMBIE = 0
    LIZARD = 1
    ALIEN = 2
    SPIDER_SP1 = 3  # Small spider
    SPIDER_SP2 = 4  # Large spider
    TROOPER = 5

0. Zombie

Appearance: Humanoid undead Movement: Slow, steady approach AI Pattern: CHASE_PLAYER - Direct pursuit Base Stats:

HP: Varies widely (20-200+)
Speed: 1.0-1.5 units/sec
Damage: 10-20 per contact

Variants:

Grey Zombie: Standard variant
Green Zombie: Brute (high HP)
Blue Zombie: Boss variant (massive HP)

Behavior: Zombies move directly toward the player using simple pathfinding. They’re the most predictable enemy type.

1. Lizard

Appearance: Reptilian quadruped Movement: Fast, erratic AI Pattern: CHASE_PLAYER or ORBIT_PLAYER Base Stats:

HP: 40-150
Speed: 1.5-2.5 units/sec
Damage: 15-25 per contact

Variants:

Grey Lizard: Standard
Yellow Lizard: Boss (high HP, slower)
White Lizard: Fast variant

Behavior: Lizards are faster than zombies and often use orbiting AI to circle the player before attacking.

2. Alien

Appearance: Blob-like creature Movement: Variable speed AI Pattern: ORBIT_PLAYER, CHASE_PLAYER, special patterns Base Stats:

HP: 30-300+
Speed: 1.0-2.5 units/sec
Damage: 10-30 per contact

Variants:

Green Alien: Standard
Purple Alien: Ghost (semi-transparent)
Red Alien: Boss (massive HP)
Grey Alien: Brute or Fast
Cyan Alien: Special AI
Brown Alien: Transparent variant

Special Abilities:

Some aliens spawn child aliens on death
Boss aliens can have ring formations

Behavior: Aliens have the most diverse AI patterns and variant types. They can orbit, chase, spawn children, or use complex formations.

3. Spider SP1 (Small Spider)

Appearance: Small arachnid Movement: Very fast AI Pattern: CHASE_PLAYER, ORBIT_PLAYER_TIGHT Base Stats:

HP: 20-100
Speed: 2.0-3.0 units/sec
Damage: 8-15 per contact

Variants:

Brown Spider: Small, weak
Red Spider: Standard or Boss
White Spider: Fast variant
Blue Spider: Special
Green Spider: Random tint

Special Abilities:

Ranged shock attack (some variants)
Timer-based AI (spawn_id 0x38, 0x39)

Behavior: Small spiders are the fastest creature type. They swarm and overwhelm through numbers and speed.

4. Spider SP2 (Large Spider)

Appearance: Large arachnid Movement: Moderate speed AI Pattern: CHASE_PLAYER, ORBIT_PLAYER Base Stats:

HP: 60-200
Speed: 1.5-2.5 units/sec
Damage: 20-30 per contact

Variants:

Brown/Yellow Spider: Splitter (splits into smaller spiders on death)
Various tints: Random stat variations

Special Abilities:

Split on death (spawn_id 0x01): Creates 2-3 smaller spiders
Ranged attack variant (spawn_id 0x37)

Behavior: Large spiders are tougher than SP1 and often split into smaller threats when killed.

5. Trooper

Appearance: Armed humanoid Movement: Moderate speed AI Pattern: ORBIT_PLAYER, ranged combat Base Stats:

HP: 80-250
Speed: 1.2-1.8 units/sec
Damage: Ranged projectiles

Behavior: Troopers keep distance and fire projectiles. They’re the only creature type that primarily uses ranged attacks.

AI Modes

From src/crimson/creatures/spawn_ids.py:22-30:

class CreatureAiMode(IntEnum):
    ORBIT_PLAYER = 0
    ORBIT_PLAYER_TIGHT = 1
    CHASE_PLAYER = 2
    FOLLOW_LINK = 3
    LINK_GUARD = 4
    FOLLOW_LINK_TETHERED = 5
    ORBIT_LINK = 6
    HOLD_TIMER = 7
    ORBIT_PLAYER_WIDE = 8

Chase Player (Mode 2)

Behavior: Direct pursuit of player position Used By: Zombies, some Lizards, basic variants Characteristics:

Moves directly toward player
No fancy maneuvers
Simple, predictable

Orbit Player (Modes 0, 1, 8)

Behavior: Circles player at specific radius Variants:

Standard Orbit (0): Medium radius
Tight Orbit (1): Close circling
Wide Orbit (8): Large radius

Used By: Aliens, Lizards, advanced variants Characteristics:

Maintains distance while circling
Harder to hit with directional weapons
Can suddenly break orbit to attack

Formation AI (Modes 3-6)

Behavior: Follows or guards other creatures Used In: Multi-creature spawns, boss encounters Characteristics:

Linked to other creatures via link_index
Moves relative to linked creature
Used for formations and escorts

Hold Timer (Mode 7)

Behavior: Stands still for duration, then activates Used By: Some spider variants (spawn_id 0x38, 0x39) Characteristics:

Stationary initially
Activates after timer expires
Used for delayed threats

Creature Flags

From src/crimson/creatures/spawn_ids.py:33-43:

class CreatureFlags(IntFlag):
    SELF_DAMAGE_TICK = 0x01       # Periodic self-damage (dt * 60)
    SELF_DAMAGE_TICK_STRONG = 0x02 # Stronger self-damage (dt * 180)
    ANIM_PING_PONG = 0x04         # Short ping-pong animation
    SPLIT_ON_DEATH = 0x08         # Splits into smaller creatures
    RANGED_ATTACK_SHOCK = 0x10    # Fires shock projectiles
    ANIM_LONG_STRIP = 0x40        # Long animation strip
    AI7_LINK_TIMER = 0x80         # Uses link as timer for AI mode 7
    RANGED_ATTACK_VARIANT = 0x100 # Ranged attack variant
    BONUS_ON_DEATH = 0x400        # Spawns bonus on death

Self-Damage Flags

Some creatures take continuous damage over time: SELF_DAMAGE_TICK (0x01): damage = dt * 60 per frame SELF_DAMAGE_TICK_STRONG (0x02): damage = dt * 180 per frame Purpose: Creates temporary creatures that die automatically (used for spawned children, special effects)

Split on Death (0x08)

Effect: When creature dies, spawns 2-3 smaller creatures at death position Used By: Large Spider SP2 variants (spawn_id 0x01) Implementation: Configured via spawn template, executed in death handler

Ranged Attacks

RANGED_ATTACK_SHOCK (0x10): Fires shock projectiles (type 9) RANGED_ATTACK_VARIANT (0x100): Fires projectiles with type specified in orbit_radius field Used By: Troopers, some spider variants, advanced enemies

Bonus on Death (0x400)

Effect: Guarantees bonus drop when killed Used By: Boss creatures, special encounters

Spawn System

Creatures spawn from a pool of 384 slots (CREATURE_POOL_SIZE = 0x180 from src/crimson/creatures/runtime.py:82).

Spawn IDs

There are 129+ spawn templates (SpawnId 0x00 through 0x80+) that define creature configurations. Examples:

0x00: Zombie Boss Spawner
0x01: Spider SP2 Splitter
0x03-0x06: Random variants (Spiders, Lizards, Aliens)
0x11-0x19: Formation spawns (chains, rings, grids)
0x21-0x2D: Specific alien variants (ghosts, bosses, etc.)

Spawn Templates

From src/crimson/creatures/spawn_templates.py, each template defines:

class SpawnTemplate:
    spawn_id: SpawnId
    type_id: CreatureTypeId
    flags: CreatureFlags
    creature: str              # Asset name
    anim_note: str | None
    tint: Tint | None          # RGBA color tint
    size: float | None         # Size multiplier
    move_speed: float | None   # Movement speed

Fixed Templates: Some templates have fixed tint/size/speed Random Templates: Many use None values, randomized at spawn time

Spawn Rate Scaling

In Survival mode, spawn rate increases over time:

Early Game (0-2 min): Slow spawns, easy enemies
Mid Game (2-10 min): Faster spawns, mixed difficulty
Late Game (10+ min): Near-continuous spawning, hard enemies

Spawn Timer: Decreases from ~2 seconds to ~0.1 seconds over 20 minutes

Contact Damage

From src/crimson/creatures/runtime.py:84:

CONTACT_DAMAGE_PERIOD = 0.5  # Damage ticks every 0.5 seconds

Creatures deal damage when touching the player: Damage Application:

Collision detected between player and creature
If contact timer expired (0.5s period):
- Deal creature’s damage to player
- Play attack sound effect
- Reset timer to 0.5s

Damage Values: Vary by creature type and variant (10-30 HP typical) Sound Effects (from runtime.py:105-111):

Zombie: sfx_zombie_attack_01/02
Lizard: sfx_lizard_attack_01/02
Alien: sfx_alien_attack_01/02
Spider: sfx_spider_attack_01/02

Creature HP and Difficulty

HP Ranges by Type

Creature Type	HP Range	Notes
Zombie	20-200+	Wide variance
Lizard	40-150	Medium HP
Alien	30-300+	Huge variance
Spider SP1	20-100	Fast, low HP
Spider SP2	60-200	Splitters
Trooper	80-250	Ranged

Boss Variants

Boss creatures (spawn_id specific variants) have:

3-10x normal HP
Larger size (1.5-2.5x)
Special colors (blue, red, yellow)
Guaranteed bonus drops (flag 0x400)

Examples:

Zombie Boss (0x00): Blue tint, 64 size, 1.3 speed
Yellow Lizard Boss (0x30): Yellow tint, high HP
Red Alien Boss (0x2C): Red tint, massive HP
Red Spider Boss (0x3B): Red tint, high HP
Shock Spider Boss (0x3A): Special ranged variant

Damage Types Against Creatures

From src/crimson/creatures/damage_types.py:

class CreatureDamageType:
    BULLET = 1   # Most weapons
    FIRE = 4     # Flamethrowers
    ION = 7      # Ion weapons
    # ... additional types

Perk Interactions (see src/crimson/creatures/damage.py):

Uranium Filled Bullets: +100% to BULLET damage
Barrel Greaser: +40% to BULLET damage
Doctor: +20% to BULLET damage
Living Fortress: +0% to +150% to BULLET (scales with stationary time)
Pyromaniac: +50% to FIRE damage
Ion Gun Master: +20% to ION damage

Strategy Against Creature Types

Zombies

Weakness: Slow movement Strategy:

Kite in circles
Use any weapon
Focus fire on clusters

Threat Level: Low (unless in huge numbers)

Lizards

Weakness: Predictable orbiting Strategy:

Lead shots for orbiting variants
Use fast weapons (SMG, Assault Rifle)
Don’t let them surround you

Threat Level: Medium

Aliens

Weakness: Varies by variant Strategy:

Identify variant quickly (color/size)
Prioritize spawners (they create more aliens)
Use area damage on groups
Boss aliens: focused high-damage weapons

Threat Level: Medium to Very High (boss variants)

Spiders (SP1 - Small)

Weakness: Low HP Strategy:

Spray weapons (SMG, Minigun, Flamethrower)
Constant movement
Don’t get cornered

Threat Level: High (swarms)

Spiders (SP2 - Large)

Weakness: Splits create more targets Strategy:

AOE weapons to kill splits immediately
Gauss Gun to pierce through
Avoid letting splitters surround you

Threat Level: Medium-High

Troopers

Weakness: Weak up close Strategy:

Close distance quickly
Use cover/movement to dodge shots
High single-target damage

Threat Level: Medium (can be very dangerous at range)

Damage Calculations - How damage applies to creatures
Weapons - Weapon effectiveness against creatures
Perks - Perks that modify creature damage
Survival Mode - Spawn patterns in survival

Source Code References

src/crimson/creatures/spawn_ids.py - Creature type IDs and spawn IDs
src/crimson/creatures/spawn_templates.py - Spawn template definitions
src/crimson/creatures/runtime.py - Creature pool and update logic
src/crimson/creatures/ai.py - AI behavior implementation
src/crimson/creatures/damage.py - Damage application logic

Overview

Game Modes

Combat System

Advanced

​Creatures and Enemies

​Creature Types

​0. Zombie

​1. Lizard

​2. Alien

​3. Spider SP1 (Small Spider)

​4. Spider SP2 (Large Spider)

​5. Trooper

​AI Modes

​Chase Player (Mode 2)

​Orbit Player (Modes 0, 1, 8)

​Formation AI (Modes 3-6)

​Hold Timer (Mode 7)

​Creature Flags

​Self-Damage Flags

​Split on Death (0x08)

​Ranged Attacks

​Bonus on Death (0x400)

​Spawn System

​Spawn IDs

​Spawn Templates

​Spawn Rate Scaling

​Contact Damage

​Creature HP and Difficulty

​HP Ranges by Type

​Boss Variants

​Damage Types Against Creatures

​Strategy Against Creature Types

​Zombies

​Lizards

​Aliens

​Spiders (SP1 - Small)

​Spiders (SP2 - Large)

​Troopers

​Related Documentation

​Source Code References

Build docs developers (and LLMs) love

Creatures and Enemies

Creature Types

0. Zombie

1. Lizard

2. Alien

3. Spider SP1 (Small Spider)

4. Spider SP2 (Large Spider)

5. Trooper

AI Modes

Chase Player (Mode 2)

Orbit Player (Modes 0, 1, 8)

Formation AI (Modes 3-6)

Hold Timer (Mode 7)

Creature Flags

Self-Damage Flags

Split on Death (0x08)

Ranged Attacks

Bonus on Death (0x400)

Spawn System

Spawn IDs

Spawn Templates

Spawn Rate Scaling

Contact Damage

Creature HP and Difficulty

HP Ranges by Type

Boss Variants

Damage Types Against Creatures

Strategy Against Creature Types

Zombies

Lizards

Aliens

Spiders (SP1 - Small)

Spiders (SP2 - Large)

Troopers

Related Documentation

Source Code References