Here are our Unlockables for GreedFall on PC. The most trustworthy items get the most 'thumbs up' from our users and appear nearer the top!
There are five companions you can meet and take with you as party members:
Kurt – Met at the start of the game.
Vasco – Met when you reach New Serene.
Siora – Met in New Serene, after your cousin sends you to meet the natives.
Petrus – Met after you do the main story quest in San-Matheus.
Aphra – Met after the main story quest where you save the Expedition survivors.
Constantin is also a temporary companion when you arrive in New Serene, but not a permanent one.
Once you have access to New Serene, the first place after the starting town, go to the coin tavern and ask about the basement. There is a character guarding the stairs to the basement, so if you talk to him and pay him 25 gold, you’ll be able to enter the basement. There’s a set of doors you can cross through to enter the coin arena.
Alternately, do the quest for the native merchant in New Serene, because that quest will automatically unlock the coin arena.
Either method should give you access to the arena.