Black Chest is an unlockable pickup in Repentance Plus, a mod for The Binding of Isaac.
Requires half a heart of damage to open.
Once opened, it will close itself after 2 seconds, generating new content, but has a 20% chance to give nothing and stay open, making it no longer usable.
Possible drops
• 37.5% - Contents of one Black Sack.
• 25% - Item from the Curse Room item pool.
• 15% - Black Rune.
• 15% - Red Rune.
• 7.5% - Contents of two Black Sacks.
Enter a Devil Room 5 times.