Enemy Perception and Alarm AI

1. Summary

Enemy behavior is governed by visible perception, patrol awareness, alert escalation, and reinforcement consequences. Vision cones show safe, suspicious, and detected states; enemies watch one another's backs, react to bodies and noises, investigate disturbances, and call alarms when suspicious discoveries escalate. Enemy categories such as Gunmen, Ponchos, Long Coats, dogs, and civilians respond differently to tools, disguises, and lures, creating the tactical puzzle of each encounter.

2. Tags

3. Design Intent / Job Story

When planning movement, takedowns, or distractions inside guarded space, I want enemy awareness to be readable and predictable, so that I can manipulate sight, sound, investigation, and alarm escalation without breaking stealth.

4. Role in Gameplay Loop

• Defines the primary stealth pressure that turns map traversal into a tactical puzzle.
• Converts player actions, bodies, noises, and line-of-sight exposure into enemy investigation or alarm responses.
• Gives reconnaissance value to vision cones, view-cone markers, patrol observation, and enemy line-of-sight relationships.
• Creates timing windows for synchronized takedowns, body removal, lures, and movement across exposed ground.
• Links failure, reinforcement, and recovery systems to detected characters or discovered bodies.

5. Preconditions

• A mission is in active gameplay and enemy NPCs or alert-capable civilians are present.
• Enemy AI has a patrol, idle, conversation, watch, or investigation state that can be evaluated.
• The player-controlled character, body, noise source, suspicious event, or target location is inside a perceivable world area.
• Line-of-sight, terrain obstruction, stance, and visibility rules can determine whether a target is seen.
• Noise-producing actions have a radius or hearing target that can be compared against nearby listeners.
• Alarm consequences are enabled for the current mission state, unless the scenario intentionally suppresses them.

6. Parameters

7. Core Rules

• Enemy vision is represented by visible cone coverage; entering or remaining in effective sight escalates from safe coverage toward suspicion and alert.
• Vision-cone color and fill communicate detection risk: green cone coverage is safe to evaluate, yellow fill indicates an enemy is becoming suspicious, and red/alert state means the enemy has identified the player position.
• The player can place or assign view-cone markers to locations, enemies, or friendly units to reveal which enemies can see that point or target.
• Enemies can watch one another; a takedown or body interaction that is visible to another enemy can raise suspicion or alarm even if the acting character is otherwise hidden.
• If an enemy sees a dead or incapacitated body in its vision cone, the enemy investigates regardless of whether the original action made noise.
• Discovered bodies can trigger an alarm and call reinforcements if the situation escalates beyond investigation.
• Noise-producing actions expose a radius or listener set; enemies inside the relevant hearing area may leave patrol or idle behavior to investigate the source.
• Very loud actions, such as high-noise firearms, can alert a broad surrounding area rather than only the nearest guard.
• If the player remains unseen after an accident or suspicious event, guards may investigate the incident and then return to normal routines.
• Enemy patrols, conversations, and attention changes create temporary blind spots and timing windows that the player can exploit.
• Movement stance changes detection timing: crouching can reduce exposure in parts of vision cones, but slow crouched movement can also leave a character exposed long enough to be spotted.
• Detection of a mission-critical character or unresolved alarm escalation can lead to combat, forced reload, or mission failure depending on mission rules.

8. BDD Scenarios

9. Edge Cases

• Player character enters a cone only briefly: confirm detection fill resets or decays according to intended rules after leaving sight.
• Multiple enemies see the same target: highest-priority alert state should win and all relevant guards should respond coherently.
• Enemy sees a body but not the player: investigation/alarm should target the evidence location, not magically reveal the player.
• Enemy hears a lure while already investigating: state priority should prevent oscillation between incompatible destinations.
• Loud weapon affects off-screen listeners: listeners outside the camera view must still react if they are inside the hearing radius.
• Body is removed while a guard is walking to investigate it: guard should resolve the missing evidence without entering a broken loop.
• Accident kill occurs in view but player remains hidden: guards may investigate the incident without treating it as player-authored unless other evidence exists.
• Player uses crouch in partial cone coverage: visibility should match terrain/stance rules and not only the cone overlay color.
• Alarm begins during Showdown or queued actions: queued actions should resolve against the current live AI state once execution starts.
• Mission failure and reload flow should handle detection cleanly without leaving AI in an alert state after loading.

10. QA Notes

11. Mechanic Dependencies

• Tactical Stealth Mission Loop (The tactical stealth mission loop depends on enemy perception to define forbidden space, patrol pressure, and the consequences of being detected.)
• Trial-and-Error Save Iteration Loop (Trial-and-error save iteration is used heavily because perception failures, alarms, and mission failures often require immediate reload and retry.)
• Disguise and Social Infiltration (Disguise and social infiltration modifies how enemies perceive a character and which enemy categories can see through social cover.)
• Showdown Synchronized Planning (Showdown synchronized planning helps the player neutralize enemies before witnesses can escalate perception into alarm.)
• Takedown and Body Control (Takedown and body control depends on perception because visible kills or discovered bodies can trigger investigation, alarm, and reinforcements.)
• Distraction and Noise Manipulation (Distraction and noise manipulation feeds perception by creating heard events that pull enemies into investigation states.)
• Movement, Terrain, and Cover Navigation (Movement, terrain, and cover navigation affect whether characters are exposed inside vision cones, blocked by obstacles, hidden, or spotted while crossing gaps.)

12. UI Links

• Mission Failed Recovery Screen - Mission Failed Recovery Screen appears when perception or combat consequences produce a hard fail state such as detection leading to critical character death.
• Right Side Alert And Hint Buttons - Right Side Alert And Hint Buttons provide persistent HUD affordances for warning or guidance states related to tactical danger and player attention.
• Tactical Spatial Markers - Tactical Spatial Markers expose enemy vision cones, alert/question markers, targeting overlays, and view-cone information that make perception state readable in the playfield.

References

1. 1.

   Desperados III (L3-8 of 50) Gameplay overview evidence for vision cones, yellow/red detection escalation, hiding bodies, body discovery alarms, reinforcements, and Showdown coordination.== Gameplay == Desperados III is a real-time tactics stealth video game, where players need to clear specific objectives while navigating through the vast maps. Players can crouch...

2. 2.

   DESPERADOS III - Know THESE Important Tips Before Playing (3:17-4:23) Instructional transcript evidence for view-cone markers, checking which enemies can see a point or target, and using line-of-sight information for tactical planning.

3. 3.

   DESPERADOS III - Know THESE Important Tips Before Playing (5:24-5:39) Instructional transcript evidence that accidents may alert guards to investigate, but if the player remains unseen guards can return to normal behavior.

4. 4.

   DESPERADOS III - Know THESE Important Tips Before Playing (7:52-8:32) Instructional transcript evidence for noise radius indicators, body discovery overriding noise, and loud actions alerting nearby/off-screen listeners.

5. 5.

   Desperados 3 Let's Play Gameplay Walkthrough Pt 12 The Wages Of Pain [1440p w/ Commentary] (4:23-4:28) Live gameplay evidence of guards detecting the player, showing vision-cone alert state and enemy movement toward the exposed character.

6. 6.

   Desperados 3 Let's Play Gameplay Walkthrough Pt 12 The Wages Of Pain [1440p w/ Commentary] (19:15-19:45) Live gameplay evidence of patrolling guards, vision cones, question-mark investigation markers, targeting overlays, and detection/reload outcomes.

7. 7.

   Desperados 3 Let's Play Gameplay Walkthrough Pt 5 Bridge At Eagle Falls [1440p w/ Commentary] (41:30-41:42) Live gameplay evidence that a thrown object/noise distraction can make a guard leave patrol and investigate the noise source.

8. 8.

   Desperados 3 Let's Play Gameplay Walkthrough Pt 5 Bridge At Eagle Falls [1440p w/ Commentary] (44:36-45:30) Live gameplay evidence for repeated detection in guarded areas leading to mission failure or combat death and retry behavior.

9. 9.

   Desperados 3 Let's Play Gameplay Walkthrough Pt 6 Closing In On New Orleans [1440p w/ Commentary] (46:21-47:02) Live gameplay evidence of yellow question-mark investigation states, enemies returning to patrol, and thrown/chicken distractions causing investigation.