so from movies and lore the Jedi become one with the force after death, What about the sith then? do the dark force users have their own after death world?

we have also seen some long dead Jedis guide the living once in movie and lore etc.., do the Sith lords do the same? or they are selfish in their death as they were in their life?

last question

as there any other way for an apprentice to gain a Darth title with out killing his/her Master?

so from movies and lore the Jedi become one with the force after death, What about the sith then? do the dark force users have their own after death world?

Darksiders are consigned to Chaos after death, if they don't become Force ghosts (see below). It appears to be the Star Wars equivalent of Hell.

we have also seen some long dead Jedis guide the living once in movie and lore etc.., do the Sith lords do the same? or they are selfish in their death as they were in their life?

Sith Lords tend to stick around as Force ghosts in their tombs or wherever, but it's out of a fear of death or an attachment to the physical realm rather than Jedi altruism. They can corrupt the living and teach them the ways of the Dark Side, as the spirit of Freedon Nadd did to Exar Kun. Most Sith are every bit as selfish and malicious in death as they were in life.

Sith can, however, be turned to the Light Side after death and become one with the Force like Jedi. Revan redeemed the spirit of Ajunta Pall in KOTOR and (SI spoilers)

last question

 

as there any other way for an apprentice to gain a Darth title with out killing his/her Master?

I think there are a few examples in the game of Darths whose masters are still alive. Darth Lachris springs to mind, though whether that's because her former master is on the Dark Council I don't know. I'm quite sure you don't need to kill your master to become a Darth.