Coming back from the dead is common place for every single person on Earth.
Downplayed: Emperor Evulz is back from the dead, but his minions had to spend years searching for that legendary artifact needed to do so. Alice, now a Retired Badass, has to come out of retirement to take down Evulz again., hopefully for good this time, so her children don't have to deal with this years later.
Justified:
The Empire has resurrection technology, and they can't wait to employ it on their leader.
Double Subverted: That was just the story that the Emperor gave. It really is him, but he doesn't want his possession of secret resurrection Phlebotinum to be common knowledge.
Parodied: No one goes to anyone's funeral because they know they'll be alive the next day. If You Die I Call Your Stuff is thrown around like "shotgun".
Zig Zagged: That new "Emperor Evulz" is the previous one's son; but it's just a masquerade made up by Evulz. However, there are only so many times he can die and come back.
People turn to God (or some being of comparable power) to bring back the dead. Said being says "no".
Discussed: "Doesn't anyone stay dead anymore?"
Conversed: "This show can't seem to kill anybody off!"
Deconstructed:
A world where everyone can come back to life after death is portrayed realistically. People who really shouldn't be around anymore are back, and there's very little that can be done about it.
Alternatively, the unchecked population growth of such a world leads to the collapse of society from overpopulation and struggle for resources.
Alternatively, repeated deaths result in complications, such as brain decay, leading frequently-killed characters to Take a Level in Dumbass.
Played For Drama: A very popular, very high-powered character in a superhero team is not only used for the Worf Effect, but actually killed by the villain. "How can we ever fight Emperor Evulz without BOB?! And if he can kill BOB, what chance do we have?!" Despite being one of the publishers' biggest hits, he either stays dead for the duration of the Story Arc, or comes back as a Deus ex Machina to finish off the weakened villain during the final battle.