Death of Lisanna Strauss

Death of Lisanna Strauss is an event that took place two years prior to the beginning of the series.

Prologue
Lisanna and Natsu were talking among each other when Happy complained that Natsu ate all his fish. Then, Mirajane and Elfman invited her to go for an S-class job where they are going to suppress the king of monsters, The Beast. Natsu was disappointed when he was being rejected by Elfman, who said that a man should protect his family by himself. After that, they went to complete their mission.

Death
Elfman used Beast Soul: Full-Body Take Over to protect Mirajane from being killed by The Beast. However, The Beast's magical power was too great and Elfman losed his grip on reality. Lisanna and Mirajane are at the scene watching him. According to Mirajane, if Elfman don't come to his senses soon, he will be consumed by The Beast. Lisanna tried to revert Elfman but he hit Lisanna with great force, throwing her a great distance. Then, Lisanna is shown in her last moments holding her sister's hand, though she actually didn't die. Mirajane was tending her wound when an Anima opened and took her into Edolas. When she regained conscious, she found herself to a different Fairy Tail Guild. Everyone at the guild believed that she was the Lisanna they knew, and welcomed her back with a smile. From their reaction, she deduced that their Lisanna had passed away. Lisanna tried to explain, but she couldn't say a word, so she pretended to be their Lisanna.

Aftermath
After their sister's death, Mirajane somehow lost much of her Magical ability and her will to fight. Mirajane also behaves differently towards Erza. Her personality changed drastically from a very feared person to a loving and caring person who treats everyone with kindness. Elfman also can't performed a Full-Body Take Over (until the battle with Sol as he don't want his sister to cry again).

In the Edolas arc, when the Anima begins to take the living beings with Magic away, Lisanna begins to glow. Lisanna tried to explain, but Mirajane and Elfman of Edolas reveals that they already knew the truth. Elfman said that they already noticed, but just couldn't say it, and apologized. Mirajane then said that she's like their Lisanna, someone who's really kind, and thus she can't let her real siblings cry anymore. As Lisanna tearfully screamed out their names, Mirajane asked her to give them their regards. When Lisanna arrives in Earthland again, she is caught by Pantherlily, suspecting her identity. Natsu and other guildmates saw them, and were surprised. Lisanna told them about the truth that she is not dead and hugs Natsu. Meanwhile, Mirajane and Elfman are visiting Lisanna’s grave, two years since her apparent 'death'. Suddenly, they were surprised to hear a voice they once knew call out to them. Turning around, their eyes widen at the sight of Lisanna running. All of them cried and hugged each other for the first time in two years.