Input "sadead" to cheat console, zombie mode start.
Re-input will stop the zombie mode.

Zombies dropping first aid kits, you can pick up it.
Press LT when you unarmed and have first aid kit to use the first aid kit to heal.
Other survivor who are not hostile by approaching them and pressing context button , who be friend and will accompany.
Press character switch wheel button to call a friends or to check the number of first aid kits you currently have.
A stun gun can be used to revive a fallen friend.
Compatible with Simple Trainers bodyguards.

Requirement
ScriptHookV
ScriptHookVdotNet

Installation
Copy "SanAndreasDead.dll" and "SanAndreasDead.ini" to "scripts" folder.

Changelog
4.4
Adjusted survivors behavior.

4.3
Spawn ammo box on ground.
Touch it, add ammo of some weapons.
When some attack hit, it explosion.
Added compatible with Aliens Come Down And Attack(version 1.3 later).

4.2
Adjusted survivors shoot accuracy.

4.1
Fix friendly survivor behavior.

4.0
Edited spawn code and survivor combat code.
May be script faster than previous version.
Adjusted survivors things.

3.1
Can change Tank and Boomer model with .ini file.
Improved survivors behavior.
Adjusted spawn probability.

3.0
Added some special zombies.
Other survivors emerge. They can be friends or hostile.
Added more configuration.

2.3
Add vehicle density configuration.

2.2
Fixed that once the zombie mode is started, some peds, activity, random events, and etc remain missing even after the end of the mode.

2.1
Fix spawned zombies becoming invisible in some situations.

2.0
Improve spawn and peds limit script.
More configuration.
Bug fix in process of Start and stop.

Known Issue
GTA5 becomes unstable when number of zombie is high.
Zombies stop when player in high altitude than ground.
Can't firing in some interior despite CanFireInInterior is true(example Vanilla Unicorn).
To avoid problems be spawn zombies with Vinewood Zombie model in some situations.
A few moving vehicle spawn despite setting 0.0 vehicle density.

Original scripts used for reference
ZombieZ V