Your blood and my name (смешанная)

What if at that infamous night in Driftmark, after Laena's funeral, it is Laenor who arrives back first to the Throne Room for the boys, instead of Rhaenyra?
Begging for a chance to protect his sons, the King of The Sea blesses Laenor and grants him poweful means to defeat the greens and to be able to fight for the birthright of his children.
But for what the gods give, they also take. Death still comes to Driftmark and Laenor is left alone to deal with the pieces until an unlikely ally comes up to him.