plz give me build for psy pvp
People don't take assassin in PvE build, because there really is no time to cast it. It's far too low overall damage to justify spending 1.5s casting.
You should take increased Agony duration ruby. If you have any extra rubies after that, you should take increased Vertex and Decomposition damage rubies as well.
If you do harder sectors, you should rank Twin and possibly even Hypnosis up, although I'm not 100% certain if that's really needed on f2p, I heard those are much easier there.
Astral Body is not worth it for PvE, just the form. 10% extra damage reduction isn't worth this many points.
Fear makes no sense in any other aspect than Suppression (which isn't viable anymore after 8.0), it takes longer time to use (due to global cooldown) than the effect will last, seems like a cruel joke from the developers.