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Items
100

On each floor, there is a high chance for a curse room to spawn, which requires taking a heart of damage to enter and exit.

There are ways to bypass the health.

100

Yum Heart

Restores a full red heart, cd 4

200

In Greed mode, the players goal is to go through floors with one central combat room and reach the boss Mega Greed.

Ultra Greed

200

A Lump of Coal

Adds flat damage to players tears based on distance traveled

300

The character Cain is identical to Isaac, except for different base stats, a lucky foot, and the lack of a d6 if unlocked.

Cain has one eye

300

Treasure Map

Reveals a floors layout, without any indicators.

400

The chapter progression goes from basement, to caves, to depths, to womb, to [beyond] (no spoilers :D)

There are alternate chapters.

400

Lucky Foot

Increases the players luck, guarantees good pills, and boosts machine payouts.

500
On the second floor of a run, provided there are no interfering circumstances, a devil deal will be guaranteed to spawn after a boss.

A devil deal is not guaranteed to spawn, rather a devil room is, which may contain 0-3 devil deals.

500
Sulfur

Grants brimstone for the current room cd 4