This comp centers around Gragas and Kha'Zix as the two main carries of the comp. You will slow roll for these two units and possibly other units like Pyke or Soraka along the way. In the late game, depending on what Emblems you have or what level you reach, you can go for higher levels of Assassin or Dawnbringer.
Go for this comp if you have a good start with copies of Gragas and Kha'Zix. Having strong items to build for these two units is also important.
In the early game, don't level in order to save up gold.
Begin slow rolling for your 3 star units once you hit 50 gold. This would be units like Kha'Zix, Gragas, Soraka, or Pyke.
Once you find at least Kha'Zix and Gragas 3, look to begin catching up in levels. You can level up quickly to 6 and 7, and use your power spike to build your economy back up.
Once your're at level 7, you can decide to save up for level 8, or continue rolling down for upgrades.
The early game is quite simple, look for Kha'Zix, Gragas, Soraka, and Pyke. If you hit an early 3-cost Dawnbringer like Nidalee or Riven, you can also drop Pyke and run 4 Dawnbringer instead.
In the mid game, your best option is to simply add in more Dawnbringers along with your core. You can also look to pick up Assassins like Nocturne to prep for 4 Assassins as well.
If you're able to get a Dawnbringer or Assassin Emblem, you can easily hit 6 Dawnbringer at level 8 by adding in another Dawnbringer like Karma or Garen. Even still, if you can hit your upgrades and have strong items, you won't need to rely on Emblems in the late game.