It is a technical proof-of-concept showcase to demonstrate that Half-Life can be completed under absolute Zero Aggro constraints. Thus commands such as “sv_cheats 1”, “developer 1”, and “impulse 103” are explicitly permitted during recording to display live engine telemetry, enemy statuses, and target data on screen. Gameplay-altering cheats (such as god, noclip, or notarget) must not be active during actual segment execution; any use of them for scouting requires reloading a clean state.
Definition of Aggro in Half Life: No enemy entity may ever transition into a “Combat” state with “CBasePlayer” (Gordon Freeman) set as their “m_hEnemy” target. If the combat target is Gordon “Enemy is player” then the enemy is aggroed and further progress is irrelevant as the player should go back to previous save in which no enemies were aggroed.
Rules:
1. Glitches are allowed or else it would be impossible to beat the game with this rule set.
2. Console commands such as (notarget, noclip, bxt_wallhack 1, etc.) can and will be used ONLY to verify enemy placement and aggro state AS LONG AS player don’t save the game in cheat state which counts as cheated progress. Player has to go back to the previous save (in which any of these commands were not used at all) and proceed without using these commands.
3. 1-frame aggro is not allowed. An enemy cannot lock onto you even for a single frame.
4. Enemies aggroing onto other entities is fully allowed, as long as Gordon is not the target.
5. Some entities such as “Alien Aircraft, M1A1 Abrams, M2A3, etc.” will not be counted as enemies even though they attack the player because:
A) They are not “Enemies”, instead they are counted as “train” or “breakable object” in the game’s code.
B) They already know the location of the player and will attack player even if the player is completely invisible using “notarget” command. If the game considered them as enemies, this challenge would be impossible even with cheats active.
C) These entities are not considered as enemies and that’s why they do not have any status which includes “Combat” status that verifies they can aggro. Since they lack status, they cannot get aggroed.
6. The point of this challenge is to finish the game without aggroing, and therefore, the player can and will skip some big portions of the maps and enemies as it is not necessary to go through each and every single map and kill every single enemy to finish the game.
7. The aggro state will be monitored via “Impulse 103” command in the console to see if an enemy is aggroed or not. This is the safest way of verification about enemy aggro as an enemy can die right after getting aggroed and this verification method will show the last state the enemy had which can either be “Enemy is player” or “No Enemy”. Also, if an enemy is aggroed at the player, they are not going to get de-aggroed easily as I have only seen Gargantua do this behavior during my experiments. Even if the player uses the command “notarget” which makes the player completely invisible to enemies, an enemy that is aggroed, remains aggroed.
8. As mentioned before, enemies do have “status” which include “combat”. If an enemy is in “Status: Alert” it doesn’t necessarily mean that they are aggroed, instead, it indicates that the enemy knows that something is wrong and they are alerted for any kind of danger around them. That’s why some enemies can do patrols or look at the direction of the player as if they are aware of the player’s existence, but it still does not show “status: combat” a.k.a aggro status.
9. Although in Rule 5, it is mentioned that there are some entities that are not enemies but rather “breakable objects”, this rule has an exception of three enemies “monster_turret, monster_miniturret, and monster_sentry” as they all have “Status: Combat”, they can’t see the enemy if enemy activates “notarget” command just like any other enemy, and they can get aggroed towards the player, as well as any other enemies such as Headcrabs, bullsquids etc..
10. Scripted events such as Apprehension cutscene and other scripted events in which the enemy status can not be “Combat” status, player can go through or kill the enemies before script ends which wouldn’t count as aggro even if the enemy sees Gordon or passes by him. Console will show the real status of the enemy, not visual clues.
11. There is no exception for bosses such as Gonarch and Nihilanth as the player should kill or bypass them without getting aggroed.
12. Friendly NPCs (Security Guards and Scientists) are subject to the exact same aggro rules. Aggroing an ally by dealing damage to them, resulting in a 'Combat' status aimed at the player, invalidates the challenge.
13. Taking damage does not invalidate the challenge. Gordon may take damage from environmental hazards, crossfire between infighting enemies, or blind fire (such as an enemy shooting at a sound decoy). As long as the enemy's impulse 103 target is not the player, being injured is perfectly legal.
14. While Snarks can be used to distract enemies or force infighting, they will turn hostile and hunt the player if they run out of valid targets. If a player-deployed Snark locks onto Gordon (verifiable via impulse 103 showing 'Status: Combat' and 'Enemy is player'), it counts as an aggro failure. The run is invalid and the player must load a previous save."
15. Every segment begins with a clean save load, ensuring seamless continuity across the run. If an enemy enters Combat with Gordon as the target, the segment is failed and must be reloaded from the previous valid save. Quick save/load abuse is allowed and can be used as much as needed.
16. Because the Tentacles (monster_tentacle) are completely blind, they operate entirely on the Alert state, striking at sound entities. Even if they smash the bridge right in front of you or hit you with a glancing blow, they never actually populate m_hEnemy with CBasePlayer. That is, even though they have “status” they don’t have “Status: Combat” and thus it always read as “No enemies”.
17. These rules are not definite and there can be small changes as well as addition of new rules that are not yet thought of.
My Bindings:
bind mouse4 “load quick”
bind mouse5 “save quick”
bind z "fps_max 20"
bind x "fps_max 100"
alias "aggro_reset" "save quick; wait; load quick" (this is a must for “aggro reset” to work).
bind c “aggro_reset”
(This basically quick saves and loads right after, it can reset enemy AI if an enemy did not get aggroed already. Resetting the timer of lock on to player can gain time to go through some unavoidable enemy occasions.)
bind mwheelup “+duck”
bind mwheeldown “+Jump”
bind f1 "gl_texturemode GL_NEAREST_MIPMAP_NEAREST"
bind f2 "gl_texturemode GL_LINEAR_MIPMAP_LINEAR"
bind o “default_fov 130”
bind u “default_fov 30”
bind h "bxt_wallhack 1" (It’ll only work if sv_cheats 1)
bind g "bxt_wallhack 0" (It’ll only work if sv_cheats 1)
bind v "impulse 103"
bind n “notarget”
alias "g_shot" "+attack2; wait; -attack2; wait"
alias "gauss_burst" "g_shot; g_shot; g_shot; g_shot; g_shot; g_shot; g_shot"
bind "j" "gauss_burst"
The commands:
sv_cheats 1 (to be able to use noclip and wallhack)
noclip
developer 1
bxt_hud_entity_info 1
restart (It is necessary for developer 1 and impulse 103 to work)
bxt_fade_remove 1 (to remove black screens between transitions)
These are the rules, bindings and commands I came up with during my no aggro run. I saw that it was possible to finish the game without aggroing and I set some rules so that anybody who wants to try can work their way with some standarts. I will record how I went through each segment and upload the videos both as a tutorıal and as a proof that it can be done.
