First : I don't belive in getting the wanted dragon from the first time 

Second : To have a better chance in getting the dragon in the second try LEAVE THE EGG THAT RESULTED FROM THE FIRST TIME IN THE HATCHERY DON'T SELL IT OR PLACE 

Third : I tried to get gummy 5 times and when I did my strategy I got in the 6th AND YOU CAN TRY AND SAY TO ME YOUR RESULT