Tainted Keeper

Tainted Keeper is a character added in The Binding of Isaac: Repentance. He is the alternate version of. Tainted Keeper is unlocked by reaching and using either the  or the  to access a special room in one of the walls while playing as Keeper.

Tainted Keeper starts with 2 coin hearts and 1 bomb. Tainted Keeper shares the same mechanics with the regular Keeper, including recovering one coin heart upon picking up a coin, as well as converting any heart pickups to blue flies. Picking up a coin to restore a heart does not add a coin to his coin counter. Tainted Keeper shoots four tears at a time, similar to the item. Whenever an enemy is defeated, a random coin is dropped that will vanish quickly. Most items encountered when playing as Tainted Keeper must first be paid for With coins, including Deals with the Devil, Angel Rooms, Boss Room items, and Treasure Room items.

Strategy and Items

 * In the standard game mode, Shops are much different and better for Tainted Keeper. They do not require a key, spawn with two Shopkeepers, and have a vastly increased stock available. At max level, they have eight items/pickups for sale, of which there will always be at least one Shop item, one Boss Room item, and two Treasure Room items. The other four terminals in the shop can be keys, bombs, cards, pills, trinkets (which will be sold for 5 cents), or more Shop/Treasure Room items.
 * This shop can rarely be replaced by a better (or worse) variant: The better variant has 2-6 more shopkeepers, Urns scattered about, two Lucky Pennies, and one more random item/pickup for sale. The worse variant has only one random sale terminal, one Shopkeeper, some Poops, and a Fly.
 * These improved shops do not appear in Greed Mode.
 * Due to this, it can be wise to skip treasure rooms for a Planetarium, as shops will typically make up the difference in items..
 * Some items do not need to be paid for. These include:
 * Mini-Boss drops.
 * Golden and Red Chest items.
 * Items spawned by beggars and machines.
 * Items spawned by other items, such as through or  card.
 * Plot-related items, including, , , , , , and.
 * This also applies to drops generated from Angel Statues while holding Filigree Feather.
 * Boss drops in.
 * Enemies spawned after entering the room (i.e. spawned by another enemy or spawned on later waves in Challenge Rooms) don't have a guaranteed coin drop.
 * Champion enemies and Mini-Bosses drop 2 coins on death.
 * Bosses drop several coins.
 * If the boss is comprised of multiple enemies (e.g. Gurglings), each of them drops fewer coins.
 * Boss Rush items must still be paid for, and doing so will start the event.
 * Because Tainted Keeper has to pay for all items, taking devil deals is often more powerful than taking Angel items. This is because taking one devil deal item will not despawn the other items, but only one item can be taken from an Angel room.
 * Sticky Nickels are able to spawn as a result of killing enemies, effectively making them impossible to collect, as it would have already disappeared by the time a bomb detonated to pick it up. would help, but it could end up in self-damage as the explosion would have to be extremely quick.
 * Coin drops from enemies are generated when a room is first generated. If an enemy that begins in the room drops a nickel, dime, or penny variant, it will drop the same coin if you leave and re-enter the room. This makes items such as and  much more useful, as they allow the player to easily leave and re-enter the desired room, allowing the player to easily generate money to fuel the run.
 * In Co-Op, all players will need to use money to purchase items if Tainted Keeper is in the game, but enemies will also drop money regardless of who killed them.
 * With this in mind, having the Blessed Penny can earn a huge amount of Soul Hearts for the players who can use them quickly.
 * This can be used to get Devil Deal items without losing health for all players.
 * Tainted Keeper can utilize Sacrifice Rooms much more reliably and efficiently than other characters, because monsters reliably generate health. This can be done by leaving regular coin drops on the floor to go pick up, or alternating stepping on the sacrifice spikes with clearing a monster room. The latter is reliable to produce coins but risky because you're always entering an unknown monster room with one health, but can be used with restarts to start a run with one or two angel room items. Keep in mind that Tainted Keeper has to pay for items in Angel Rooms that you may get at the 6th sacrifice, though the item drop you may get at the 7th sacrifice will be free.
 * Having a good speed stat may be very beneficial, in order to pick up coins before they disappear.
 * Golden Pennies are able to spawn as a result of killing enemies. It still despawns like a normal coin unless picked up, in which case, any subsequent spawns will not disappear.

Favored Items

 * strongly attracts coins dropped by defeating enemies to Tainted Keeper, doesn't affect other coins.
 * acts as a slightly less effective version of this.
 * effectively allows for free damage as long as you can get to a dropped coin.
 * / allow for Tainted Keeper to retrieve dropped coins that are otherwise inaccessible, such as ones over a pit or a gap.
 * Most Penny Trinkets are powerful from the sheer amount of coins Tainted Keeper is able to earn.
 * Burnt Penny and Flat Penny allow Tainted Keeper to obtain large amounts of keys and bombs.
 * Burnt Penny in particular is especially powerful; in a room with enough enemies, it is possible to gain infinite money and bombs by killing most enemies in the room, then bombing your way out of the room to reset it.
 * Charged Penny allows for quickly charging active items, and can serve as a pseudo-.
 * Counterfeit Penny can give an additional coin for each one you pick up, helping you gather money much more quickly and allowing you to afford more items.
 * Cursed Penny allows Tainted Keeper to farm infinite money. Killing an enemy drops a coin, which will teleport him to a different room and reset the current one.
 * Rotten Penny allows Tainted Keeper to amass a large amount of blue flies.
 * works on any purchasable item.
 * Because coin drops are determined by the seed, the D7 can be used to reset a room with a valuable coin to get it twice. Can additionally be used in Shops and Secret Rooms to refight Greed and Super Greed, allowing for large coin generation.
 * guarantees 1-3 coins when clearing rooms if they would otherwise have no drops, and increases max number of coins to 999.
 * Door Stop effectively allows for infinite money with enough patience. Tainted Keeper can leave 1 monster alive in a room, leave, and re-enter to collect even more coins from killing enemies. Since the coin drops are determined by the seed, you can wait until an enemy drops a nickel or dime to do this to spend less time.
 * works very well to address Tainted Keeper's low health, able to grant up to 4 additional coin hearts, and up to 12 additional containers if you also have . Keep in mind that you do have to buy most of your things, and that lowering your coins below each threshold will also remove a coin heart.
 * Like, Tainted Keeper can technically have unlimited coin hearts by swallowing many copies of Mother's Kiss.
 * has a chance to double the coins dropped from killing enemies.
 * gives you stat upgrades every time you purchase an item, which is available much more often with Tainted Keeper than with other characters.
 * can be used to kill every enemy in the room, then you can gather their dropped coins to replace the ones you spent. Since enemies can also drop nickels and dimes, you'll tend to gain money over time.  The item is especially useful with high damage, or on later floors where you don't need to save your money to buy items.
 * automatically draws in dropped coins. Broken Magnet and Super Magnet are also good substitutes.
 * / add additional shops for Tainted Keeper to purchase items and pickups in.
 * can combine with the large number of coin drops in general to increase Tainted Keeper's damage steadily, even more so with.
 * 's damaging aura helps compensate for Tainted Keeper's low tears stat, and can destroy large amounts of enemies at short range so you can focus on collecting the money.
 * 's downsides aren't as severe, as you are usually already close to enemies to collect dropped coins.
 * Silver Dollar grants you access to two extra shops after Mom, which is extra valuable with Tainted Keeper's stronger shops.
 * reduces prices of all items, even outside the shop.
 * has a chance of allowing Tainted Keeper to safely regain lost health and collect coins after getting hit; this is very good for killing large groups of enemies.
 * can be used to break the game in a room with many enemies by taking damage and killing enemies to heal back the lost health. Fanny Pack may provide bombs when you take damage, allowing you to continuously bomb out of the room and re-enter.

Situational Items

 * HP Up items, save for Greed's Gullet and Mother's Kiss, don't do anything. Unlike regular Keeper, Tainted Keeper can never have 3 hearts. Only take them if your health has been reduced in any way (such as by taking ).
 * While or  would be items normal Keeper would want to stay away from, Tainted Keeper could potentially benefit from these items considering the large amount of coins he is able to produce.
 * butt penny is useful for pushing away and poisoning enemies, but can cause other coins to be pushed away and time out.
 * has a chance to grant or remove 1 coin heart, making it a more favorable item if an HP up is nearby but can be detrimental if there isn't.
 * is generally a bad item, as it usually pays out with 7 cents and costs 15. However, if it is on sale, it is almost always worth it it pick up, as you will at least get back the money you spent on it.

Disfavored Items

 * Because Tainted Keeper only has Coin hear ts, Blessed Penny and Bloody penny will only spawn flies, effectively turning into less effective versions of Rotten Penny. Additionally, currently does not work with Tainted Keeper, as every item needs to be purchased.

Interactions

 * Multiplied enemies will not drop coins: Only an amount of coins equal to the original amount of enemies in the room at the start can be dropped.
 * The pennies dropped from killing enemies have a chance to be sacks instead. The sacks do not flash and disappear.
 * Similarly to how the chance for dimes and nickels to appear are determined by the seed, sacks are as well: rerolling the enemies in a room with will result in them dropping sacks again if they had the first time, with the same exact contents inside the sack every time.
 * Hematemesis pill makes Tainted Keeper spawn coins instead.
 * will heal Tainted Keeper.

Trivia

 * Through his abilities and appearance, Tainted Keeper is the equivalent of Super Greed as is to Greed.
 * The achievement for unlocking Tainted Keeper is "The Miser", a possible title for the character.
 * A miser is someone who obsessively hoards money and refuses to spend it, the former of which fits Tainted Keeper's penny-pinching playstyle.