It's every easy, I completed it without losing 1 map/lvl. You must just start with getting alot cells, if you have more cells then the enemy you're about unstopable...
I also hate things that lowering stats, but I had a good solution for it. I maxed out 3 stats I believe and the others where 0 (or 1). I had like max attack, defence and 1 other stat (not sure whiths it was).
But it is quite a good game and I had fun playing it. But I think it was to easy...
PS. I don't think anybody who has problems beating this game know now how to. :P