I had a great game the other day - got pretty big and had a little helper that I kept giving some food to, saved them when they were about to be eaten by giving them enough to eat their pursuer. Then later I ended up shrunk down and they did the same. We ended up in a corner with whoever was smallest "baiting" people to chase them for the big guy to move in and feast - great fun. Ended up transferring all y mass to them when I quit.
I'm trying to perfect the art of firing viruses to bring down the giants. It lets you go on the offensive against a much bigger opponent or defend yourself when you are getting chased - if you are surrounded by lots of big cells then making one of them split will focus all the other attention on that one and let you go free.
I have a sense that people remember more when you save them from a bigger cell vs when you help an already bigger cell catch someone.