Early Gunslingers + Pirates Team Comp & Build
This setup is according to many, one of the most reliable early game setups in the game. Start by acquiring both Tristana and Graves, both of which are 1 gold units and very common early on. Getting these two gives you the tier 1 Gunslinger buff, which gives all Gunslingers a 50% chance to fire additional attacks at a random enemy. Having this buff will significantly increase the power of both Graves and Tristana. Notice, if possible, build the Red Buff item for Graves as soon as possible. As his basic attack is splash, he spreads the true damage debuff to multiple enemies at once. Pyke and Gangplank are great additions to this early game setup, as they are both Pirates and will give your team the Pirate buff: Each round, you earn up to 4 extra gold setting you up for late game. These two units are rarer than Tristana and Graves, as they are a 2 gold unit and a 3 gold unit. Furthermore, as Gangplank is also a Gunslinger, you can quickly obtain the tier 2 Gunslinger buff if you acquire another Gunslinger, Lucian or Miss Fortune. Of these, you are probably looking at Lucian, a 2 gold unit, as Miss Fortune is a 5 gold unit, and only appears late game.
Team comp example: Tristana, Graves, Pyke, Gangplank, Lucian