Complex sentence: One of the characters who has come back repeatedly from death is Beric Dondarrion, The Lightning Lord, and what has happened with him echoes with some of the other characters who have come back from death.
Split into simpler sentences: One of the characters who has come back repeatedly from death is Beric Dondarrion, The Lightning Lord. I think you see echoes of that with some of the other characters who have come back from death.