User blog comment:B214/Shin DxD 1 discussion/@comment-33939194-20181017214709/@comment-33939194-20181018074923

Being Heavenly Dragon class doesn't mean Ddraig won't win. Yes, Vali manage to put up a fight but that doesn't mean Crom won't beat Ddraig. Remember that Azi Dahaka and Apophis are also Heavenly Dragon class but were still defeated by by Issei and Vali. Vali had a harder time against Crom then he did against Azi.

The reason Crom gets so much hype is because he's the only dragon that's not a dragon god that's stronger than Ddraig and Albion. Considering the reputation that Ddraig and Albion have in the story, that's a big deal. Ishibumi has been giving a trend on the level of opponents to give Issei.

First there were Dragon kings who are said to rival the Maous. Second, comes the evil dragons that Ophis warned about and how they are potentially stronger than the Dragon Kings. Third, you have Apophis and Azi who is said to rival Ddraig and Albion and now you have the strongest evil dragon that is said to surpass them. Going by the flow of the story it only makes sense.