This card derives from the death of a creature infected with aflatoxin. It replicates (growing exponentially) every turn AT THE END OF THE TURN. That means if you have this and your opponent either has a fire buckler out or has infected them all the previous turn, you're not getting other cells. Also, it creates other 1/1 no skill cells, no matter how you boost one.
The growth is (normally) 1->2->4->8->16->Full.