The biggest tip I can give to using this build effectively is to NEVER play scared. Artanis was built to excel in places where others fail. With typical heroes, when they are half way dead they are no longer the monsters they are when they are at high health. With Artanis its the opposite. When he is half dead, his effectiveness is doubled. So do not be afraid to engage in certain spots because his trait becomes a factor once you soak enough damage. Even if you don't spec into tankiness.

Other notes....

1) Use the phase prism to initiate fights instead of just finishing fights.
2) Stay aggressive once the trait kicks in. The CD is always in your favor the longer you fight.
3) Use the purifier beam to finish kills. The damage is more likely to take in those scenarios.
4) If not to finish, purifier beam can also be used to peel tanks.
5) Artanis is ALWAYS one kill away from starting up a potential team wipe. Especially at 20.