I found a way, well...with some creative engineering, to get UNLIMITED Gnome kills, red or pink crystals (they kinda look both lol) and life force of any kind.
We all know the DOWNSTAIRS gnome cage at the everlight facility (where you got the green hive.
Here is what you do, and thanks to my "creative engineering", you don't have to do a single thing.
What you need:
1 copy of overlord 2 1 xbox 360 1 wireless/wired controller 2 pieces of scotch tape. Any tape is fine.
Have about 25+ brown minions with you, position yourself facing the open gnome gate directly, then open it. Hold down right trigger to constantly release your minions. Once they leave your side, they go and kill and return with whatever drops. Its IMPORTANT to park yourself facing the absolute middle because sometimes lifeforce or crystals tend to get on the sides of the wave of minions and the minions don't automaticly grab them. Once this is down, carefully tape the right trigger button down tightly so it doesn't come undone. Put your controller down and wait as long as you want. I recommend an hour at least.
Every minute, I got about 20 of each life force, 2-3 crystal and the gnome kills!
Please let me know what you guys think of my method, and I will remind you not to stand TOO CLOE to the gate. The minions need a berth of about 7-8 feet (or 6-8 steps) from the gate in order to do their job and not allow the gnomes out.
I've used my method for about 3 hours now, probably less. I didn't keep track. I've gotten 900 of each life force, plus 125 crystals There is one tiny down side to this method. Seems that there are no blue gnomes present. So no blue life force. Also, you may need lots of tape, it can come undone after a while. vibration in your controller unless you turn it off.
I recommend leaving your 360 and the game running overnight once, by morning you'll have a couple thousand life force and even a couple hundred or more crystals. I'm going to do so tonight.