Sure fire way to get red key?

[willy bammy]

Anyone know yet what item pool the red key is in? My dumbass didn't realize I could use it when I first got it, I thought it was some important thing for the boss so I didn't get my first B side character

[CrypticKhaos]

You can get it in curse rooms. You can also drop a trinket in the boss or item room before you start going back up floors and they'll turn into the a shard of the Red Key so you can use it once.

[willy bammy]

Originally posted by ๖ۣۜCrypticKhaos:

You can get it in curse rooms. You can also drop a trinket in the boss or item room before you start going back up floors and they'll turn into the a shard of the Red Key so you can use it once.

I figured that out the very next run I did after posting this, very freakin cool