This comp utilizes a Chosen Dusk to hit 6 Dusk in order to beef up Riven as the main carry. Jhin is also a good secondary carry who can utilize Dusk Spatula very well.
Go for this comp if you find an early Chosen Dusk, find good Riven items, or find an early Riven.

Stage 2
Before Krugs
Level up to 4 early if you want to start a win streak. Level up to 5 to try and continue the streak.
If you're weak in the early game, you can opt to save gold and lose streak instead. Level up to 5 at Krugs if you don't think you can beat them.
Stage 3
Before Wolves
At Round 2, level up to 6 regardless of your start. Put together the strongest team you can.
Stage 4
Before Raptors
At Round 1, level up to 7. Roll down to stabilize your comp if you are weak. Afterward, save up to hit level 8 and complete your comp.
This comp transitions out of Sharpshooters very well. Vayne is used in the final comp and Nidalee can be used to transition into Warlord as an early game synergy.
In the mid game, you want to find Kennen as your carry. He synergizes very well with Keepers like Jarvan, and after this point, level up further to find your 4 cost units.
Dusk Spatula is not required for the comp, but it helps a lot. Jhin is a very potent secondary carry, but you can also run late game units like Sett or Kayn in place of Jhin. This also allows you to drop Vayne if you go for a different carry.
In an ideal world, you would find your Chosen Dusk as Thresh, Riven, or Cassiopeia. Getting a Chosen Vayne will be fine, but won't be as useful as finding a higher cost Chosen unit.
Kennen is a strong mid game unit to run as he provides good damage and Keeper. You can also have him hold Dusk Spat until you find Jhin or another strong unit like Sett or Kayn.