Minecraft systemd script, uses mcrcon instead of screen

minecraft@.service

[Unit]
Description=Minecraft server - %i
After=local-fs.target network.target

[Service]
User=minecraft
Group=minecraft
UMask=0027

EnvironmentFile=/etc/mcrcon.conf
KillMode=none
SuccessExitStatus=0 1

NoNewPrivileges=true
PrivateDevices=true
PrivateTmp=true
ProtectHome=true
ProtectSystem=full

WorkingDirectory=/opt/minecraft/%i
ExecStart=/usr/bin/java -server -Xms512M -Xmx2048M -XX:+UseG1GC -XX:+CMSIncrementalPacing -XX:+CMSClassUnloadingEnabled -XX:ParallelGCThreads=2 -XX:MinHeapFreeRatio=5 -XX:MaxHeapFreeRatio=10 -jar current-minecraft.jar nogui
ExecStop=/usr/bin/mcrcon -P ${%i} -H ${SERVER_IP} -p ${RCON_PASSWD} stop

[Install]
WantedBy=multi-user.target

# Copy this file to /etc/systemd/system/
#
# Create a new directory in /opt/minecraft to hold each game. In this example:
#   /opt/minecraft/serverdirectory1
#   /opt/minecraft/serverdirectory2
#   ...
#
# Rename the Minecraft .jar to current-minecraft.jar
#
# Start a game in each directory to create all necessary files, and accept the EULA
#
# In each directory, modify server.properties:
#   server-ip=<your server's IP>
#   server-port=<your game's port, unique for each game>
#   enable-rcon=true
#   rcon.port=<a unique port for each game, NOT same as server-port>
#   rcon.password=<an admin password you choose, same for each game>
#
# Install mcrcon:
#  $ cd /opt/minecraft
#  $ git clone https://github.com/Tiiffi/mcrcon
#  $ cd mcrcon
#  $ gcc -std=gnu11 -pedantic -Wall -Wextra -O2 -s -o mcrcon mcrcon.c
#  $ sudo cp mcrcon /bin/bash/mcrcon
#
# Create /etc/mcrcon.conf
#   RCON_PASSWD=(password you set in server.properties)
#   SERVER_IP=(IP address of this server)
#   <serverdirectory1>=<rcon.port from serverdirectory1/server.properties>
#   <serverdirectory2>=<rcon.port from serverdirectory2/server.properties>
#   ...
# Note that <serverdirectory> is case-sensitive, and relative to /opt/minecraft.
#
# Enable the service:
#  $ sudo systemctl enable minecraft@serverdirectory1
#  $ sudo systemctl enable minecraft@serverdirectory2
#
# Configure your client to connect to each game server:
#   Server Name = Something that refers to your game
#   Server Address = <your server's IP>:<your game's port>