In the Character Creation thread, it says a player can have as many characters as he/she wants. My question is, can these characters cooperate and travel together in a similar manner to Hylian Shield's old companion characters, or for the sake of fairness in avoiding certain situations am I required to have each character act on his own?
Your characters may roleplay with each other, yes. However, their reward becomes limited, due to balance issues. The rule is as follows: "The rewards of a quest are determined using a scale of rupees. By default, every quest has the same reward: 40 rupees for every player involved, and 10 rupees for every character involved. A single player's rupee reward caps at 80, and a group of any size has a cap of 200 rupees attainable." Essentially, what happens is your first character will receive a total of 50 rupees for the quest by himself. If a second of yours joins, this rupee reward, in total, is increased to 80 rupees between the two characters. Finally, a third character would mean no increase in the rupee reward, etc. etc.
Its actually: 40 per Player 10 per Character So you can have a party of four of your own characters before it hits the max limit of 80 rupees (which have to be divided between the party of four characters (on average it would be 20 each, but its your choice how you split the 80 rupees). You can have more then 4 characters in the party, but the limit is stil 80.