-When you have the perk and take fatal damage, you do NOT die.
-Instead, you are teleported to a dark, isolated area.
-After a short teleport animation, you respawn as a ghost at a spawn point.
-In ghost mode:
-Your screen turns red and desaturated.
-You have a blood overlay.
-You are given a B23R with limited ammo.
-You have 30 seconds to find your tombstone.
-A tombstone is left where you "died".
-If you reach the tombstone and hold use, you revive.
-If you fail to reach it in 30 seconds, you die for real.
-When you revive, you become "Clone 2".
-First time you become Clone 2:
-You get a TMP.
-Your score is set to 1500.
-Later revives:
-You keep your saved money for that form.
-You keep weapons you picked up in ghost mode if you don't already have them.
-You can switch back and forth between your original self and Clone 2 each time you die and revive.
-The perk icon changes to a ghost icon while you are in ghost mode.
-You cannot buy the perk again if you already have it or if you have an active tombstone to recover.

TUTORIAL

1 Put the files in the corresponding folders.

2 In zombiemode_perks_custom
Open this file and add the following line in the init() function:

add_perk( "specialty_parralel", 4069, true, "custom_vending_parallel", "custom_vending_parallel_on", "custom_vending_parallel", "specialty_parralel0", "revive_light", "Parallel Echo", 2, "mus_perks_doubletap_sting" );

3 — your_map.gsc
Add in the main() function:

level thread maps_zm_custom_whoswho::init();

And in your map's precache function:

maps_zm_custom_whoswho::custom_whoswho_precache();

4 — Modify perk_hud_create() in _zombiemode_perks_custom.gsc
IMPORTANT: to prevent perk icons from overlapping each other, you must replace the existing perk_hud_create() function with this pyramid version using 40x40 icons:

perk_hud_create( perk )
{
if ( !IsDefined( self.perk_hud ) )
{
self.perk_hud = [];
}

hud = create_simple_hud( self );
hud.foreground = true; 
hud.sort = 1; 
hud.hidewheninmenu = false; 

if( level.zombie_vars["zombie_perk_hud_type"] == "cw" )
{
	hud.alignX = "center"; 
    hud.alignY = "bottom";
    hud.horzAlign = "center"; 
    hud.vertAlign = "bottom";
    hud.x = 0;
    hud.y = hud.y - 20;
}
else
{
	hud.alignX = "left"; 
	hud.alignY = "bottom";
	hud.horzAlign = "user_left"; 
	hud.vertAlign = "user_bottom";

	// ====================================================
	// PYRAMIDE : 13 perks repartis en 4 rangees
	//   Rangee 0 (bas)  : 5 icones (index 0-4)
	//   Rangee 1        : 4 icones (index 5-8)
	//   Rangee 2        : 3 icones (index 9-11)
	//   Rangee 3 (haut) : 1 icone  (index 12)
	// ====================================================
	index = self.perk_hud.size;
	spacing = 44;
	row_height = 44;

	if ( index < 5 )
	{
		row = 0; col = index; base_x = 0;
	}
	else if ( index < 9 )
	{
		row = 1; col = index - 5; base_x = 18;
	}
	else if ( index < 12 )
	{
		row = 2; col = index - 9; base_x = 36;
	}
	else
	{
		row = 3; col = 0; base_x = 72;
	}

	hud.x = base_x + col * spacing;
	hud.y = -70 - (row * row_height);
}

hud.alpha = 0;
hud fadeOverTime(0.6);
hud.alpha = 1;

// ====================================================
// ICONE AGRANDIE : 40x40
// ====================================================
hud SetShader( level.zombie_perks[ perk ].perk_shader, 40, 40 );
hud scaleOverTime( 0.6, 40, 40 );

self.perk_hud[ perk ] = hud;

if( level.zombie_vars["zombie_perk_hud_type"] == "cw" )
{
	x_start = -1 * ((self.perk_hud.size * 36) / 2);

    keys = GetArrayKeys( self.perk_hud );

    for( i = 0; i < keys.size; i++ )
    {
        self.perk_hud[keys[i]].x = x_start;
        x_start += 36;
    }
}

}

5 in your mod.csv put this :

material,zmb12_perk13_texture1
material,~-gzmb12_perk13_texture1
material,specialty_parralel0
material,specialty_parralel1

5
On your map in Radiant, you must place 6 entities:

Entity Targetname Role
script_model ,targetname custom_whoswho_buy_trigger (the model 3d)

put this in a blackbox_____
script_struct ,targetname parallel_echo_fx_spot Point where the teleport animation plays
script_origin ,targetname teleport_perk13_1 Player 1 position
script_origin ,targetname teleport_perk13_2 Player 2 position
script_origin ,targetname teleport_perk13_3 Player 3 position
script_origin ,targetname teleport_perk13_4 Player 4 position

put this toward initial spawn points or elsewhere in your map____
script_origin ,targetname spawn_fantome1 Ghost respawn position 1
script_origin ,targetname spawn_fantome2 Ghost respawn position 2
script_origin ,targetname spawn_fantome3 Ghost respawn position 3
script_origin ,targetname spawn_fantome4 Ghost respawn position 4

️ Place the teleport_perk13_* in a dark, isolated area (the "black box") and the spawn_fantome* at your map's initial spawn points.

6: Compilation
Open your mod in Launcher.exe
Click Build Mod
Wait for compilation
Launch the game

!! if you don't have a _zombiemode_perks_custom, add the file in yous maps folder !!

Thanks wathcing this tutorial

Dowload : https://mega.nz/folder/PJ0j2bbL#hRXaSNGOohluFWUCll1s_w

Video : https://www.youtube.com/watch?v=7j_NrMO8q6E