Shhh🤐 it's a great farm. Something changed recently. The only bad thing is no one reads text chat, I try to direct to the free loot cave every time. I swear I've gotten like 10 in a row. It's got to be over 50% for the room chests to drop another keycard immediately. I've gotten them from other chests in the bonus zones, but it's much rarer. But the rooms themselves, have a keycard?... get another keycard.