The prophecy: theory given most recent chapter

"Darkness has fallen upon the land. The blood of the dragons will revive once again, and the ancient pact will be kept.

When the four dragons are gathered, the sword and shield which will protect the king shall awaken, and the Red Dragon shall restore the dawn at last."

"The blood of the dragons will revive once again". Is this because the dragons will have lost their powers- will they revive their powers then after their sent to earth to keep their pact? Is the pact the one of protecting the king or something else we dont know of?

Are we certain the "four dragons" are the dragon warriors? Im starting to think its the dragons in the chalice. Also, I couldnt help realising while reading the newest chapter that the yellow dragon wasn't there. And they referred to Zeno as a fragment of the yellow dragon instead - is that cause he has the blood or does the dragon exist in Zeno somehow?
We're definetly getting close to the end of the prophecy, and are the sword and shield about to "protect the king" from the dragons once all 4 are gathered maybe?

Im not sure this is just some thoughts I had given the information this chapter and last chapter.