Your main quest in The Outer Worlds is helping Phineas Welles revive the colonists on the Hope to thwart the Board’s plans, so you might think that handing him over to the Board would be the end of the game. The Outer Worlds has a way of letting you continue after making that choice, though. If you choose to go this route, it will shorten the game somewhat, but you’ll still have quite a few quests ahead of you. The big difference is that you’ll be working as a lackey of the Board to help its members bring their plans for the colony to fruition.
You’ll get the chance to turn Phineas Welles in the first time you go to the Groundbreaker. To get there, you have to first complete the questline on Terra-2 to retrieve a power regulator and use it to get your ship into orbit. That means choosing between giving more power to Edgewater or the Botanical Lab on the planet, but the choice you make here won’t affect your ability to join the Board later, so go with your gut.
Once you get to the Groundbreaker, you’ll need to meet with a man named Udom Bedford to turn Phineas Welles in. You’ll find him in the Halcyon building in the central courtyard of the Groundbreaker, just before you get to the engine room. The garish Halcyon building is easy to recognize since it stands out among the more run-down style of the rest of the Groundbreaker.
When you try to hand Phineas Welles over to Udom Bedford, he’ll first think it’s too good to be true, so you’ll have to prove your devotion to the Board. That means that you’ll first have to go to Monarch and give control of a transmitter there to the Board. It’s mostly the same quest you would have to complete next if you were siding with Phineas, so there’s no real change to the game here. Just like on Terra-2, you can resolve the quest any way you want and still be on track.
After you complete Monarch, things start to diverge. Udom Bedford will give you passage to Byzantium, the seat of power in Halcyon, where you’ll immediately get to meet with a high-ranking official. From here on, you’ll be doing some very unsavory quests for the Board, mostly involving assassination and other dirty deeds. You’ll also miss out on the quests that Phineas would have given you at this point, which also takes place on Byzantium.
The final quest of the game remains mostly unchanged, except in the end you’ll be siding with a corporate official rather than Phineas. If you beat the game this way, you get a different ending showing the success of the Board’s plan and your position in the new hierarchy. Following the Board’s plan leads to a much darker outcome for The Outer Worlds, but it’s viable if you want to explore that option.