Ok, after experimenting with my v4, I have concluded a few things to get a good character. Not that there are characters that are bad, but I am talking about the characters Masktchi and Gozarutchi. Ok, from the moment my tamagotchi is born, I never fed it any snacks. At all, no snacks. If it's happiness bar went down, I played a jump rope until the number reached 6, then I lost on purpose, and it makes go up one heart. Do that until each heart is filled. Never overfeed it, and try to maintain a weight under 30 lbs. I always fed it sushi, and nothing else. I play games with it every day. It should turn into something good. Right now it is a teenager and it is itchigotchi.