I got up to 7th on my own.... Annoying game.
Getting up to top #1 isn't actually hard.. The problem is STAYING there.
You can't get that big if you're playing by yourself, because you'll be too big a target as the merge-time does not change.
So it's time that causes you to merge together? I just kept accidentally splitting at the wrong times and kept getting most of me eaten. I got to 8th, then got almost totally eaten, then got up to 7th, then got eaten again then couldn't be bothered to rise up again.
Yes,, there's a time counter.. Which is why you never want to SPLIT, unless you're getting a GOOD-DEAL out of it, because once you split, there is a significant rise in risk of being eaten..
Your first split should happen at 40 and 80.. Don't bother trying to eat someone at those values, just use the larger area to collect dots faster.
Once you go above 80, do NOT split until 300, at the 300 point keep collecting dots, but you may begin to attack some cells..
Get all the way up to 600, and this point is where you can relax a little bit, because you'll be bigger than the majority..
Once you hit around 1000+ you should be close to top 10... ALWAYS avoid confrontation of similar sized cells, for example, DO NOT fight with someone that's 1500 or 1000, if you're 1100.. Because there's really nothing to win, and you spend alot of time, and taking alot of risk of getting blown up (virused, the yellow thingy)
ONLY confront people of similar size if they come at you, and you're closer to a VIrus bubble, always strike first,, FIRST STRIKE is always better..