Immunity Protocol Mechanics Guide: Combat & Evolution

Core Combat Loop: Move, Shoot, Evolve

Immunity Protocol centers on a simple but deep loop: you control an immune cell sentinel, your weapon fires automatically, and you must survive escalating pathogen waves. Unlike traditional shooters, your primary input is movement and positioning. The auto-fire system lets you focus entirely on dodging enemy attacks and navigating the collapsing bioscape.

Your sentinel's effectiveness depends on how well you manage upgrades, skill choices, and symbiont equipment between waves. Each run challenges you to adapt to evolving enemy types and environmental hazards.

Weapon Evolution System

Your weapon is not static. As you defeat enemies and collect experience orbs, your weapon gains levels and can evolve into more powerful forms. Evolution paths vary based on the upgrades you pick.

Key aspects of the system:

• Base weapon: Starts with a simple projectile attack.
• Evolution triggers: Reaching certain kill counts or collecting specific upgrade modules.
• Branching paths: You can choose between spread shots, piercing beams, or explosive rounds.
• Synergy: Combining certain upgrades unlocks hidden weapon forms.

Skill Upgrades and Builds

Between waves, you visit a skill selection screen. You can choose from a pool of passive and active abilities. These skills define your playstyle and survivability.

• Passive skills: Increase stats like movement speed, health regeneration, or damage resistance.

• Active skills: Provide temporary boosts, such as a shield, a speed burst, or a targeted attack.

• Rarity tiers: Common, Rare, and Epic skills appear as you progress further.

• Prioritize movement speed early to avoid enemy projectiles.

• Choose damage resistance if you struggle with boss waves.

• Active skills with crowd control are invaluable against swarms.

• Always check for synergy icons that indicate powerful combinations.

Symbiont Equipment System

Symbionts are special equipment pieces that grant unique passive bonuses or active abilities. You can equip up to three symbionts at a time, found as loot during runs.

Symbiont types include:

• Offensive: Increase damage, fire rate, or add elemental effects.
• Defensive: Grant shields, health leech, or damage reduction.
• Utility: Improve loot drops, experience gain, or movement abilities.

Enemy Types and Wave Scaling

The game features a variety of pathogen enemies that scale in difficulty. Early waves consist of slow-moving bacteria. Later waves introduce fast viruses, armored fungi, and boss pathogens.

Understanding enemy behavior is key:

• Bacteria: Slow, high health. Best handled with piercing weapons.
• Viruses: Fast, low health. Spread shot or explosive rounds work well.
• Fungi: Stationary but spawn smaller enemies. Prioritize them early.
• Bosses: Appear every 5 waves. They have unique attack patterns and require focused dodging.

For a full list of enemies, check our enemy types guide.

Survival Strategies for Endgame Waves

Reaching the final waves requires a solid strategy. Here are essential tips:

• Keep moving: Standing still is a death sentence. Constant strafing helps avoid projectiles.
• Prioritize threats: Eliminate fast enemies and spawners first.
• Manage resources: Collect health orbs and experience only when safe.
• Upgrade wisely: Focus on one weapon evolution path rather than splitting upgrades.

For beginners, our beginner guide offers a step-by-step walkthrough of your first run.