光与暗的门扉

Jorbs

Early in Act 1 I like upgrading two cards quite a lot. Even an upgrade on a Strike or Defend can be very valuable when your deck is full of weak Starter cards. Later on, once I already have a few good cards, I tend to use this as a card remove, to help me draw those good cards more quickly.

Baalorlord

A simple but quintessential choice in Act 1: do you upgrade or remove? If you're in the very early floors, it's often better to upgrade to handle upcoming combats more easily. Even upgraded Strike/Defend cards do well in Act 1. If you're close to the end of the Act and already have a few upgraded cards, the removal is more tempting. My usual rule of thumb is to remove if you know you can already win the Boss fight of the Act and to upgrade if you can't.