Here is the hidden math that the game does not shout at you:
It is the equivalent of selling your car for $50 because you don't like the color. The Gold and ISO you receive are a microscopic fraction of what you will lose in future duplications, signature levels, and shards. how to sell champions on marvel contest of champions
You now know the technical steps. But the true mastery of MCOC is knowing when not to use a feature. Here is the hidden math that the game