Oga is now the strongest at Ishiyama. He fought Tojo using only his raw brute strength unlike when he fought Kanzaki or Himekawa. This definitely proves that he is the strongest. It was a battle fought with only true grit and muscle. What comes out it is that Baby Beel and Oga now share a relationship of trust. If Oga asks Baby Beel to dispel the Zebel spell he probably would. It would also seem that Oga has finally resigned himself to being Baby Beel’s parent.
This definitely the best fight of them all. I just wonder what will happen next? As considering that I have read none of manga I don’t know.