Before you proceed!

1. make sure your Ubuntu server has ipv6 disabled, otherwise players cannot join through server list. (read below)
2. make sure you got root access
3. game should be downloaded inside "/root" folder like "/root/polyfield"

-------------- UPDATE v0.7.5+ -----------------

the game folders and files are created next to game files:
- /root/Polyfield.x86_64  >> game file
- /root/editor            >> editor maps folder 
- /root/ServerConfig.txt  >> server config
- /root/banned-users.txt  >> banned users

the game will migrate the files on first run.

-------------- INSTALL GAME -------------------

you need to install these:
apt-get install screen unzip libc6-i386 lib32stdc++6

install for 32bit: (Optional)
apt-get install libncurses5:i386

download the game:
wget https://polyfield.net/builds/Polyfield_v0.7.5_Linux_Update4.zip

unzip the game:
unzip Polyfield_v0.7.5_Linux_Update4.zip

give it execute permission:
chmod +x Polyfield_v0.7.5_Linux.x86_64

---------------- GAME CONFIG ------------------

run the game once to create the folders:
./Polyfield_v0.7.5_Linux.x86_64

close the game after 1 min:
Ctrl + C  or  Ctrl + Z

check "ServerConfig.txt" file appears:
ls
Enter

edit the config:
nano ServerConfig.txt

save:
Ctrl + O
Enter

download manually if it doesn't appear: (or check your directories)
wget https://polyfield.net/builds/ServerConfig.txt

-------------- RUN SERVER --------------------

create a screen so you can close the terminal:
screen -S test

run the game in screen:
./Polyfield_v0.7.5_Linux.x86_64

detach from screen:
Ctrl + A + D

close the terminal.

----------------- ENJOY ---------------------

later accessing the game:
screen -r test

see the running games:
top

close:
Ctrl + C  or  Ctrl + Z

--------- Download some good maps ----------- (Optional)

move to the location:
cd /root/editor

remove all maps:
rm -r *

download back:
wget https://polyfield.net/builds/Server_Maps.zip

unzip:
unzip Server_Maps.zip

----------------- BAN-LIST ---------------------

users get banned for 90 days.

server saves the ban list here:
/root/banned-users.txt

close the game before editing.

------------------ CRONJOB ------------------ (Optional)

edit crontab:
crontab -e

restart every 2 hours:
0 */2 * * * pkill Polyfield ; ./Polyfield_v0.7.5_Linux.x86_64 &

save:
Ctrl + O
Enter

---------------- DISABLE IPV6 ------------------

create a file:
nano /usr/local/sbin/disable-ipv6.sh

place these:
/usr/sbin/sysctl -w net.ipv6.conf.all.disable_ipv6=1
/usr/sbin/sysctl -w net.ipv6.conf.default.disable_ipv6=1
/usr/sbin/sysctl -w net.ipv6.conf.lo.disable_ipv6=1

Ctrl + O + Enter >> Save
Ctrl + X >> Exit

give perm:
chmod +x /usr/local/sbin/disable-ipv6.sh

apply to cronjob:
0 * * * * /usr/local/sbin/disable-ipv6.sh

apply by hand:
/usr/local/sbin/disable-ipv6.sh

check: (it should show nothing)
ip -6 addr show

------------------ SYSTEMD ----------------- (Optional) (This will keep the app running if crashed)

create file for auto-run service:
sudo nano /etc/systemd/system/game.service

copy & paste into the file:
###########################################
[Unit]
Description=Game Server
After=network.target

[Service]
ExecStart=/root/Polyfield_v0.7.5_Linux.x86_64
Restart=always
RestartSec=5
WorkingDirectory=/root
User=root
RestartForceExitStatus=0
#Environment=GAME_VAR=value

[Install]
WantedBy=multi-user.target
###########################################

reload & start:
sudo systemctl daemon-reload
sudo systemctl enable game.service
sudo systemctl start game.service

check status:
sudo systemctl status game.service

see live logs:
sudo journalctl -u game.service -f