There is an event, I got, to plant a new one. I'm not sure of the requirements, but it happened about a year after the first Legion invasion was defeated.

But that wouldnt give you immortality back, atleast in lore, also why we need the pandas to cometh

If you want to be immortal get to level 9 on any magic class. As for the pandas, they are simply an April fools joke that refuses to die despite being almost twenty years old.

there are no pandas yet, thats a future major update in the far future

thanks for the info

to retain immortality for night elf do not let burning legion reach and successfully besieged nordrasil. after old world tree destroyed night elf permanently lose immortality except few high class character.

@Valsalan Pandaren have been in the lore since the Warcraft games tho.

the pandas cameth @Virsia :P