I found this one pretty easy to do on Rendering plant on solo. Go to the lake at the bottom right of the map, you can bring up your map with the
button. Drown them in the water then swap to another character with the d-pad and revive them. Rinse and repeat. The default strikes is 2 ( which stands for times you can go down and be revived) on the third down it will kill you instantly. Easier if you have a friend be the monster so you dont have to worry about him messing with you though.
x VeNoMz x V3 brought up a good point that lazarus' lazurus device does not count toards the revives you must actually go up to them and pick them up.
x iKrueLTyyy brought up a good point if you can turn the man eating eels map effect on so that they go down faster. Also make sure strikes are set to infinite so that you dont have to worry about them dying out right.