[b450]

> There's no objectively good cards, it is always relative to your deck and relics, and the upcoming boss fight

This is really the key. A card always has value in context. A good player will take, for example, a Disarm, and say "this solves Book of Stabbing". The important point is that Disarm doesn't have to be useful in every fight, but it adds a solution for _some_ fights to the deck. Good players focus on the specific set of problems the deck has to solve, discounting future challenges relative to imminent ones, and add tools for those fights. Good players also tend to highly value card draw and deck manipulation to enable searching the deck for the right card when it's needed. Depending on how effectively you can cycle the deck, adding tons of cards to a deck is often a good strategy. For example, a deck with Corruption and Dark Embrace basically doesn't need to worry about the deck bloating at all because the whole deck can be searched in one turn.