This talent selection looks to pair En Pointe at level 1 with Fright at level 4 and Mind Devourer at 7 which can allow Orphea to apply slows which can guarantee tip strikes of Shadow Waltz.

Once you hit 7 you can start adding damage value to Dread, which is good because as you'll see with the other selections, you're trying to empower your next basic attack by 150% using Overflowing Chaos.

At 10 Crushing Jaws can apply more pressure between your empowered basic attacks and can be very useful as a finisher.

At 13, with Abyssal Symbiosis things really get interesting because you can get up to two empowered basic attacks against the same enemy if you use Q->Q->E->AA->W->AA. If you manage to hit the tips for each Shadow Waltz, that is quite a lot of extra damage.

At 16, you are either looking at Dead Magic or Bond of Anguish. Keep in mind that two fully empowered AA will deal an additional 230 Spell Damage in an area near your target.

Finally, Eldritch Conduit is the preferred choice here. Because of your Symbiosis, Chomp will instantly give you 80% spell power for 10 seconds.