Anyone who's seen the finale episode “The Diamond of the Day, Part 2” knows that Merlin did not have a happy ending.

Does Morgana die in Season 4?

Finding his courage, Arthur strikes Camelot and overthrows Morgana. Arthur takes his crown back and marries Gwen, who finally becomes Queen of Camelot. Wounded and banished, Morgana almost dies, but at the very end, the little dragon Aithusa heals Morgana before flying away.

How did Morgana die?

Morgana catches up with Merlin and Arthur and drives their horses away, but she is killed by Merlin wielding Excalibur.