Trading

A lot of people have expressed an interest in being able to trade cards, gold, or relics. Putting many hours in together in the spire mod, I've found the mechanic quite fun. It opens up a lot of possibilities and theory crafting.

For those of you who want to see trading implementated into the game, how would you go about doing it?

For those of you who don't want trading added to the game, how do you think this would negatively affect multiplayer?

Personally, I think there are plenty of valid ways to add trading from events/shops/or rest site options, and im not opposed to drawbacks to this mechanic for balancing.