Simple Headshot System

#include <a_samp>
public OnPlayerTakeDamage(playerid, issuerid, Float:amount, weaponid, bodypart)
{
    // If body part = HEAD and WEAPON = Sniper and Health <= 100 (if you have something like "god" system)
    if(bodypart == 9 && weaponid == WEAPON_SNIPER && GetPlayerHealth(playerid, health) <= 100.00)
    {
        GameTextForPlayer(issuerid, "~r~HEADSHOT", 4000, 4);
        GameTextForPlayer(playerid, "~r~HEADSHOT", 4000, 4);
        SetPlayerHealth(playerid, 0.0);
    }
    return 1;
}