Complex sentence: It is shown that he has completely abandoned the Jedi way after the New Sith Order attacked the Jedi Academy on Ossus, although he still encounters other Jedi, as well as the ghost of Luke Skywalker.
Split into simpler sentences: It is shown that he has completely abandoned the Jedi way after an attack by New Sith Order on the Jedi Academy on Ossus. Nevertheless, he still encounters other Jedi, as well as the ghost of Luke Skywalker.