Here we have part 4 for you guys, with part 5 just around the corner!
Torrent 720p version from teamgaki.com:
Just download the torrent once and use the .ass file every time to watch the new subs!
Subtitles: Batsu 2014 – No laughing Defense Force (Parts 1 to 4).ass @ Teamgaki.com
Torrent: Batsu 2014 – No laughing Defense Force full.torrent @ Teamgaki.com