Red Redemption

Red Redemption is challenge #44. The goal is to defeat Mother. This challenge is unlocked by unlocking Tainted Jacob.

Level generation in this challenge works very differently than normal. Tainted Jacob begins in a starting room without doors, and other rooms are generated in small clusters that are disconnected from each other and must be located by using the Red Key. Each floor generates like a Curse of the Labyrinth floor with one Shop, two Boss Rooms and two Treasure Rooms, each connected to a group of normal rooms. Defeating either Boss will spawn a trapdoor that leads to the next chapter. Chapter 4, however, will not have special rooms other than the single Boss room where Mother resides. All rooms may be from any floor in the current chapter (for example, in Chapter 1, rooms may be from the Basement, Cellar, Burning Basement, Downpour, or Dross). This applies to both pre-generated rooms and new rooms made using the Red Key.

The Red Key also works differently than normal. It starts in Jacob's consumable slot, and can be used any number of times with no recharge. The Red Key can not be used to create a door to the I AM ERROR room.

After using the Red Key 20 times in a single floor, Dark Esau will spawn. The Red Key's charge bar displays how many uses it has left until this happens, rather than the item's actual charge. Another Dark Esau will spawn every 5 additional uses of the Red Key, as long as Jacob is not in his The Lost form. If he is, no more Dark Esaus will spawn.

Sacrifice Rooms will grant Tainted Jacob rewards as usual, but they will not teleport him to the Dark Room.

Knife Piece 1 and Knife Piece 2 are not required to finish the challenge, however Knife Piece 1 can still be encountered in an item room.

Strategy

Try to avoid depleting Red Key's charge without covering a lot of ground. Each red room entered will be able to check the adjacent three rooms to see if they are normal rooms, so spacing apart paths of red rooms in straight lines, at least two rooms apart, will grant the most information per use of the key.

This challenge is like Blackjack, as it's preferable to visit as many rooms as possible, as they give you consumables or even extra items, while making sure you don't go over the allotted amount of uses of the Red Key given per floor before Dark Esau spawns.

Most special rooms have at least one normal room next to them that are free to go into. Mapping abilities will show you the locations of either the special rooms or the clusters of rooms where they can be found, allowing you to minimize aimless wandering and potential Dark Esau encounters.
- The Compass, Crystal Ball, and Treasure Map are the most useful items for this purpose, allowing an optimal route to be planned on every floor to visit as many rooms as possible to get more items and therefore a greater chance of winning.
- Book of Secrets is also useful to help find where the regular rooms, item rooms, shops and boss rooms.
- Sol acts like a weaker version of The Compass for the purposes of this run, as it reveals one boss room, and beating the boss will show the rest of the rooms on the floor.
- Many cards can help reveal parts of the map, so items that increase the amount of cards found such as Deck of Cards are useful. Obtaining XXI - The World or XIX - The Sun will identify all rooms for a floor, while IV - The Emperor, IX - The Hermit, and XVII - The Stars cards will locate a specific important room via teleportation, and Blank Card will allow the reuse of these cards. Similar utility could be gained from Rune Bag to obtain the Rune of Ansuz, but they will be considerably scarcer compared to cards.
- It is very risky to take unidentified Pills during this challenge, as getting an Amnesia will make it much harder to find your way around.

Due to the fact that starting items in this challenge cannot be changed, rerolling your character through the use of the D4, the D100, or other means such as a Dice Room is safe to do, unlike using the Clicker

Any means of teleportation works surprisingly well in this challenge: random teleportation will NOT teleport you to any red room, including already opened ones. This will almost guarantee that you will teleport into either special rooms themselves (treasure, shop, boss, etc) or rooms adjacent to them, saving lots of red key charge in the progression. Teleport! and Teleport 2.0 both work, while Broken Remote is the most efficient while in combination with certain active item that can be infinitely used (like Guppy's Paw).

Satanic Bible is a strong item, as it acts as a reliable source for health and Devil Deal items.

If you are okay with Dark Esau chasing you, you can use it 5 more times before another one spawns, as well as an extra means of damage for the boss of the floor.

You do not need to fight Mother to finish this challenge, it is enough to fight any boss on the last floor. Using Book of Revelations will turn Mother into Conquest or Death, and the fight will still drop a trophy. The same strategy can be used with a IV - The Emperor? card; it also drops a trophy while having the boss be any available for Chapter 4. It is also possible to find a trapdoor from We Need To Go Deeper! or a Rune of Ehwaz to go to Sheol and fight Satan, where the challenge will end.

Do not transform into other characters during this challenge, as this will remove the Red Key and eventually make you unable to progress through floors.
Using Mama Mega! is a potential full clear of a floor, but is risky if Jacob has turned into his The Lost form, especially in Caves, where mushroom explosions may kill you on the room instantly.

Crystal Key is very useful in this challenge because it has a chance to open red rooms after a room is completed, saving Red Key uses.
If possible, try not to let Dark Esau spawn on the last floor because otherwise you'll have to fight Mother while he annoys you. Since Mother is a bullet hell boss, you'll have a hard time surviving.

Most types of special rooms can be encountered as red rooms, so if you are willing to explore (considering the risks it implies), you might find very useful stuff such as more Treasure Rooms, Shops etc.
If Anima Sola is used, the Red Key fully recharges, allowing infinite uses without having to worry about Dark Esau.

Notes

Secret rooms of any type will not be generated in this challenge.
Unlike usually, The Boss Rooms might be connected to more than one non-red room.
Although you cannot get Angel Rooms or Devil Rooms from bosses, it's still possible to encounter them as red rooms.
Birthright will split all Dark Esaus in two. However, it does not split Dark Esaus that spawned prior to pickup.
Planetarium can be generated in this challenge.