Beginner guide to awareness, aggression, and enemy alarms for urban survival in Heart of the Machine.
Survival in the City: Aggro, Awareness and Alarms
You’ll learn how enemies perceive your units, what triggers aggression, and how to manipulate the system to your advantage whether through stealth, deception, bribery, or outright force. From security clearance levels and trespassing mechanics to the consequences of being Marked Defective, this guide covers everything you need to know about avoiding, mitigating, and surviving the city’s complex web of hostility and alarms.
Awareness of Units
Aggro, in this and other games, broadly means:
- A specific enemy unit is aware of one of your units.
- That enemy unit desires to attack your unit.
However, both awareness and hostility come with substantial nuance, which is what the rest of this article explores.
Positive (Lack of) Awareness
Most of the time, both you and enemies are mutually blind to each other. Here’s why.
Blending In and Other Methods of Being in SightA unit may blend into the environment due to several factors:
- They resemble other androids or vehicles and aren’t acting unusually.
- They look unusual but are wearing a hoodie to conceal their features.
- They look unusual but are too adorable to be perceived as a threat (Adorable perk).
- They are in the shadows and hard to see (Shadowdweller or Expert Shadowdweller perks).
- They appear as if they belong (Authoritative perk).
- They are a convincing Mimic human, making them indistinguishable from others.
In these cases, enemies and humans see your unit but don’t register them as a threat. How This Applies in ReverseThe city is densely populated with humans, vehicles, and aerial traffic. Units may appear to “materialize” as they emerge from the crowd and become noticeable. Your machine perception filters out the noise the same way humans ignore most of your units unless they actively stand out.
Active Cloaking or Liquid MetalCertain units can activate abilities that render them completely invisible, even to enemies who were previously looking at them:
- Cloaking: Renders a unit completely invisible.
- Liquid Metal Form: Spreads the unit thin in the environment, making them undetectable.
Neutral Awareness
- If a unit lacks any perks that allow them to blend in, they are a noticeable entity.
- Choosing the Defiant stance makes units stand out aggressively.
- A unit may appear unfamiliar, but not outright alarming, leading to curiosity rather than hostility.
Example: “That mech looks like a new model, but it’s just standing there. I wonder who manufactures that?”
Negative Awareness
Some units immediately attract negative attention from everyone, typically due to being Innately Alarming.
- Any armed enemies within range will likely open fire immediately.
- Normally passive guards may engage from across security walls.
Being noticed doesn’t always mean being attacked. Just like you might ignore two corporations fighting in the distance, enemies may see your unit without acting on it. Awareness alone isn’t aggro—there has to be hostility as well.
Trespassing
Before we discuss anger, let’s cover trespassing, as it’s a separate mechanic.
Security Clearances
There are five security levels (plus a “no clearance” category):
- Sight (L1) – Basic clearance, accessible to regular android traffic (farms, oil sites, small checkpoints).
- Oversight (L2)
- Secret (L3)
- Top Secret (L4)
- Interior (L5)
Your starting units can freely enter L1 areas. Anything beyond that requires special handling.
Free Movement
You can force entry into any location by switching a unit to Combat stance.
- The Active stance prevents you from moving into restricted areas unless you have clearance. This helps prevent accidental aggro.
- If an enemy is already aware of one of your units in a restricted area, additional units can enter without switching to Combat stance.
Consequences
Entering a restricted area without clearance results in:
- Immediate aggro from all guards and security forces at that location.
- Increased hostility from corporate-affiliated units.
However, nearby installations do not react unless they share the same security network.
- Example: If two military bases are next to each other, entering one will not alert the other.
Additionally, passive blending methods (hoodies, mimics, etc.) no longer work while trespassing.
Avoiding Those Consequences
If a unit steps into a restricted area and you don’t want to escalate aggro, leave immediately.
- Enemies will stop targeting your unit if it exits without retaliating.
- However, they will fire on you during the retreat via Attacks of Opportunity.
- Retaliating escalates the situation further, leading to alarms and reinforcements.
Anger
Before discussing alarms, let’s address anger—how it escalates and what it means for your units.
Marked Defective
This is not the same as aggro, but it has similar effects.
- A unit is Marked Defective when it attacks a corporate authority figure (e.g., SecForce, military).
- Attacking gang members, civilians, or religious figures generally does not trigger this—unless they have corporate ties.
Once Marked Defective:
- Blending in stops working.
- The unit is now at Neutral Awareness (or Negative Awareness if already Innately Alarming).
- Authority figures actively hunt the unit.
- This applies only to corporate forces, not independent factions.
Since most enemies in Chapter One are corporate, the distinction might not be clear until later.
Paying Off Your Fines
Violence is tolerated in the city as long as you pay for it.
- You can clear Marked Defective by paying a fine at a licensing agency.
- The cost is insignificant compared to what you steal, but functionally represents a hefty sum in-world.
However:
- Paying the fine does not reset unit identity.
- Enemies who were already angry at that specific android will remain hostile.
Wiping Your Identity
To fully reset anger:
- Ambush another android and steal its registration.
- This takes two turns and permanently clears Marked Defective.
- Scrap the unit and replace it.
- Costly, but guarantees no lingering hostility.
- Use high-stealth methods:
- Toxic Cloud (Shadowdweller perk).
- Cloaking or liquid metal form.
- ID Scrub (available in Chapter Two).
Angered Cohorts
Enemies belong to cohorts—cross-sections of a faction.
- Attacking a unit makes the entire cohort hostile toward the attacker.
- This hostility remains until the unit wipes its identity or dies.
A unit can still blend in if not Marked Defective, but cohort members will recognize its city ID and attack on sight.
- Alarms
Guards at military bases, mines, and other key locations behave differently than regular units.
They will not leave their post unless:
- Your unit is Innately Alarming or otherwise drawing negative attention.
- Your unit trespasses into their designated area.
- The alarm is active for their facility.
If the alarm is inactive, guards:
- Will not leave their assigned area.
- May fire across fences but won’t pursue.
Activating the Alarm
An alarm triggers if you:
- Damage a guard inside a restricted area.
- Continue attacking while the alarm is active (extends the duration).
However:
- Missing a shot on a mech does not trigger an alarm.
- Rebels do this all the time, and corporations find it more intimidating to ignore ineffective attacks.
- Attacking non-guard units inside a base does not trigger an alarm.
Deactivating the Alarm
If an alarm is active near your base, you have two options:
- Bribe the guards using the Disable Alarm option in StreetSense.
- Costs 5 strategic resources (cost increases with repeated use).
- Wait it out.
- Alarms naturally deactivate after 5 turns if no further attacks occur.
Be careful not to re-trigger the alarm immediately after it deactivates.