On Unity SMP, deaths are only considered final if it is written into the story as final. A character could die an infinite amount of times without a final death if it is not written into the story as final. Here are the rules of deaths.
Deaths are only canon if they happen in lore and are distinct deaths. Large massacres such as the Final Showdown do not count every death as canon.
Deaths are only final if they are written as final.
When they die, a character is sent to the afterlife dimension.
When a character dies, they must wear a desaturated ghost-like version of their skin.
If a ghost canonically dies once, they are dead for good with no coming back.
Although, dead players would not have any gameplay restrictions as long as they aren't in lore.
Every ghost gets one extranormal ability, although some ghost haven't shown any abilities.
Ghosts tend to not have memories of being alive but sometimes remember bits and pieces of their lives.
Biglegs has the ability to make a ENDLIFE.exe potion which can erase any player from existence permanently.
On Unity SMP, resurrection can be used by certain characters to revive dead players. Here are the rules of resurrection.
Resurrection is performed by combining flesh, blood and belongings of the deceased,
Canonically, only a few people actually know how to perform resurrection.
A revived player has all the memories of their past life and their time in the afterlife.
People Who Can Perform Resurrections
Matt is the first person on Earth-1 to discover the resurrection ingredients. When he was revived by Kostina, he left and revived every dead anarchist including Julius, Chyll, Big O and SwerveSoldier.
Kostina learned how to revive people from Matt and used it to revive Matt and Noah.
Phil used resurrection to revive Kostina.
Afterlife and Hell
Based on how a person spent their life, they will be sent to either the Afterlife or Hell.
Hell can be reached from the Afterlife by going down to the bedrock.
If an alive player is transported to Hell without physically dying, they are still considered alive.