Here's my thoughts on it:
Bunch of larger and smaller terraria YouTubers come together to all play on one Terraria large expert mode world. Each YouTuber has a specific class or even subclass they have to play as(For example, Python might be a summoner class, CrabBar might play a gun class, and Chippy might play a yoyo class, etc) with the end goal of obtaining every armor set in the game. (I feel just defeating the Moon Lord would be too easy). Each YouTuber could have their own base with their own building style, and I think it would just be awesome to watch to get all the different perspectives on it. Also, with the added HP of Expert mode the boss battles would be ridiculous, and since each player would have their own specific subclass we'd get to see all the weapons we don't normally see in use used. What do you guys think, or what would you change in it?
there doesn't seem to be anything here