hydro_on()
{
    objective_lights = [];
    for(i = 0; i <= 3; i++)
    {
        objective_lights[i] = getent("objective_light"+i, "targetname");
        wait(0.5);
    }
    flag_init("water_retrieved");

    cost = 50000;

    trigger = getent("hydro_switch", "targetname");
    trigger setCursorHint("HINT_NOICON");
    trigger setHintString("The power must be activated first");

    thread water_get(trigger);

    flag_wait("electricity_on_nick");
    objective_lights[0] setModel("zombie_zapper_cagelight_green");

    wait(0.5);

    trigger setHintString("You need to get water first");

    wait(0.5);

    flag_wait("water_retrieved");
    objective_lights[1] setModel("zombie_zapper_cagelight_green");

    wait(0.5);

    trigger setHintString("Engine is starting up.... Please wat 1 minute and 45 seconds");
    objective_lights[2] setModel("zombie_zapper_cagelight_green");

    wait(105);

    trigger setHintString("Press &&1 to Activate Hydrolic Engine [cost: "+cost+"]");

    while(true)
    {
        trigger waittill("trigger", player);
        if(player.score >= cost)
        {
            player thread maps\_zombiemode_score::minus_to_player_score(cost);
            player playsound("cha_ching");
            objective_lights[3] setModel("zombie_zapper_cagelight_green");
            trigger delete();

            flag_set("hydrolic_on");
            break;
        }else
        {
            player playsound("no_cha_ching");
        }
        wait(0.5);
    }
}