Hm, I can't solve it with just a Phagocyte. Eventually they die off way before 1000h are reached. Are you making any adjustments? I've tried a few, none worked.
Praizmlet has found a pretty reliable way to solve this challenge in the current CL version in an unintended way with just Phagocytes. I think this might warrant an update after all. I know the difficulty is already high otherwise, but I think it would be the right move in this case. What do you think?
Your solution is very good to my genome!
Perhaps instead of decreasing salinity, the challenge objective should be higher than 50 cells. The food bits are huge here, so any moderately efficient smart organism has no excuse for holding fewer than 100 cells, in my estimation. Even 200 may not be too much to ask for.
If nothing else, the phagocyte-only organism is a good unintended solution. I wonder if something similar might also work in "Flat Earth", given the easy mobility and rich nutrients there.