Pills

**Pills** are pickups that can provide useful or inhibiting effects. They take up the same slot as cards and runes.

At the start of each run, an effect is randomly assigned to each color of pill. The pill effect for each color will remain constant throughout the run. (However, it is possible for , , , or  to reassign some of the effects, such that 2 different colored pills will have the same effect.) Pills start the game unidentified (unless the player is holding  or ); their effect is shown as "???" when picked up. Upon using a particular pill for the first time, its effect will be revealed and all subsequent pills with the same color will have their effect shown as well. The set of pill effects for any given run is usually known as the *pill pool*.

* The pill pool for each run has increased from 9 to 13.

## Pill Classes

Repentance introduces the mechanic of pill classes. Internally, pills are given a class from 0 to 3 and a polarity that reflects their influence:

Pills in class 0 have little to no impact on a run overall, while pills in higher classes are correspondingly more influential, class 3 pills having effects as significant as permanent stat changes.
Classes that end with + or - denote a positive or negative effect, otherwise considered neutral.

This mechanic is used to balance the pill pool and avoid having too many negative or positive pills. Polarity is used by certain items to determine which pills to convert.

## Gold Pills

Repentance introduces **Gold Pills** (or Golden Pills). Using them will give a random pill effect. Gold pills only have a chance to be "used up" upon using them, which means that you can often use them many times before they finally disappear.

* Unlocked by:  Defeat Mega Satan as  Tainted Cain.
* The possible effects are all effects that aren't in the run's pill pool, which means if you see an effect from a normal pill, you will never see it from a golden pill.
* Items such as  or  which alter pill effects also work on the effects of this pill, allowing many beneficial effects to be stacked with little risk. Effects altered by these items may overlap with the effects in the run's pill pool; for example, a run might have Tears Up in the pill pool and Tears Down outside of the pill pool, which will be turned into Tears Up due to the effects of the item.
* Gold Pills have an ID of 5.70.14.
* A Gold Pill can also be a Horse Pill. Golden Horse Pills use the Horse Pill effect on every use.
* Golden horse pills are most likely the rarest pickup in the game with a 0.06% chance of spawning instead of a normal pill.
* If a Golden Pill uses the 'Vurp' effect, and no other pill was used prior, another golden pill will drop.

## Horse Pills

*Repentance* introduces **Horse Pills**. These are larger versions of the standard pills with a more powerful effect, but only appear very rarely. Unique sound effects can be heard when they are used, and the narrator's normal spoken voice lines are instead shouted using a different voice.

* Unlocked by:  Defeat Mega Satan as  Tainted Eve.
* All items that work with pills work identically with horse pills.
* A horse pill with a given effect has the same color as the normal pill does.
* Horse pills have an ID of the normal ID + 2048 (i.e. 1 << 11). For example, a white-blue pill has an ID of 2, so the horse pill version would have an ID of 5.70.2050.
* It is also possible to have a golden horse pill. (It has an ID of 5.70.2062.)

## Probabilities

Pills that spawn with a sub-type of 0 (i.e. a random pill) will have the following probabilities:

* Random normal pill - 97.86%
* Specific normal pill - 7.53%
* Gold pill - 0.7%
* Random horse pill - 1.43%
* Specific horse pill - 0.11%
* Horse gold pill - 0.01%

## Notes

* Among the attribute modifying pill effects, only five of the seven visible attributes are covered: health, range, tears, speed, and luck. Both shot speed and damage can't be altered by pills.
	+ Shot speed can now be altered with pills. Damage can now also be altered with pills with .
* If a "Health up" pill is used while Isaac has 11 empty red hearts and one non-red heart, The non-red heart will be replaced with an empty container, killing Isaac.
* Having , , or  and using a "Re-Lax" pill has a chance to spawn Golden Poop,  Black Poop, or  White Poop, respectively.
* If the item  is picked up and then lost in any way, such as rerolling by the  or a Dice Room, or dropping it as  Tainted Isaac, pills will remain fully identified for the rest of the run, but negative pills will not be converted.
* Pill effects have a chance to be narrated upon use, as do cards and runes.
* Currently, the "Retro Vision" pill effect can crash the game on some machines, resulting in restarting the current floor when the game is continued.
* The "Addicted!" pill will have no effect if Isaac has .
	+ Despite this, if one takes both the "Addicted!" pill with "Percs!" in the same room, Isaac will take a full heart of damage from all sources.
* Using an "Infested!" pill on Red Poop will spawn blue spiders and the red poop will regenerate.
* If a Tiny or Large Champion monster drops a "One Makes You Small"/"Larger" pill and either pill is not in the current pill pool, an existing pill will be overwritten. If the chosen pill was already identified, the new pill will also be.
* "R U A Wizard" does not affect  Lilith's Incubus.
* Isaac's hitbox can be reduced to 30% of original, which is achieved after 6 One Makes You Small pills. Further pills will only make him visually smaller, with no additional benefit.
* Using a "Gulp!" pill while holding two trinkets (with  or ) will cause both trinkets to be absorbed.
* Magdalene's starting pill will override one of the pills in the current run's pill set if it doesn't exist in it (Speed Up for *Afterbirth+*, or Full Health in *Repentance*). The pill that is converted is dependent on the run's seed.
	+ This only applies if the run is started as Magdalene or if Magdalene is chosen as a Co-op partner, not if Isaac turns into Magdalene using .
* All golden pills in the run have a shared sequence of effects they activate, so reversing the effects of one golden pill through  and consuming another golden pill will activate the same effects.
* If a Vurp! effect is activated by a golden pill, it will spawn the last non-golden pill taken by Isaac, or a golden pill if no non-golden pills have been taken by Isaac in the run.
* If a Marked Skull is destroyed while Isaac is holding , it will spawn a Telepill instead of . If Telepills doesn't exist in the current run's pill set, one of the pills in the run's set will be turned into Telepills. The pill that is converted is dependent on the run's seed.
	+ All other pills with the same color as the Telepill spawned will also be converted into Telepills for the rest of the run, even if they're currently being held by Isaac. This can also override Magdalene's starting Full Health pill.
* While transformed into The Lost by a White Fireplace, Health Down pills turn into Health Up pills, regardless of Isaac's number of red heart containers.

## Strategy

* There are 24 good effects, 14 neutral (sometimes good/sometimes bad) effects, and 12 negative effects. This means taking mystery pills is usually beneficial. However, you should consider not taking one if an effect like Hematemesis or Tears Down would ruin your run.
* Use of unidentified pills is recommended for outside of combat as Hematemesis, R U a Wizard?, Paralysis, Addicted!,  X-Lax, and  I'm Excited!!! can be detrimental mid-fight. However,  I'm Drowsy...,  Something's wrong..., Lemon Party, Bad Gas, and Pheromones are useless outside of combat.
* Percs! can be used in the Sacrifice Room to reduce the damage Isaac takes, potentially allowing him to do more sacrifices. However, if Isaac is teleported to the Devil/Angel room, he loses the effect.
* The invincibility effect from Power Pill and  Feels like I'm walking on sunshine! can be utilized to get into Curse Rooms, play Blood Donation Machines and  Confessionals, or use Devil Beggars and  Hell Games without taking any damage.
	+ Percs! can be used to reduce damage from these from chapter 4 onward.
* can be used to effectively generate infinite golden pills, as the trinket's ability to respawn collectibles applies with every use.
* Taking only golden pills in a run can allow for infinite golden pill generation by repeatedly activating the Vurp! effect.

## Unlockable Achievements

* Huge Growth - Increase in size 5 times in a single run via , "One makes you larger" pills, , etc..

* Marbles - Use 5 Gulp! pills in one run ( uses count).

* Lachryphagy - Collect 10 "Tears Up" items or pills in one run.

* Lil Spewer - Have Isaac die to his own explosion from , , or a Horf! pill.

## Trivia

* The Vurp! pill is a portmanteau of the words vomit and burp.
* Power Pills activating the Gamekid effect is a reference to Pac-Man, in which the "Super-Pac" powerup is obtained by eating a Power Pellet.
* "I Found Pills (and Ate Them)," "R U a Wizard?," and "I can see Forever" are all image macro memes.
* The Feels like I'm walking on sunshine! pill is a reference to the 80s song Walking on Sunshine.
	+ Furthermore, creator Edmund McMillen made in 2010 a video with the same name, although it doesn't feature the actual Walking on Sunshine song.
* Balls of Steel is a reference to *Duke Nukem*; it is one of Duke's more famous quotes.
* Explosive Diarrhea is extremely loud and forceful diarrhea. In the original game, the message that displayed when the pill was activated was "Oh No!". The pill name and effect are likely a reference to Atomic Bomberman where a pickup of the same name would cause the player to drop bombs behind them uncontrollably for a short duration.
* Shot speed effects were introduced in The Binding of Isaac: Eternal Edition, after the release of Rebirth. They were finally added to Rebirth in the Repentance DLC.
* Hematemesis is a medical term for vomiting blood.
* Lemon Party is a reference to internet shock site featuring a group of elderly men performing oral sex, peeing on each other.
* "Puberty" having a negative sound effect is a tongue in cheek connotation to how unpleasant that period in life can be.
* Friends Till the End! was originally in the Wrath of the Lamb but removed in Rebirth, then put back into Afterbirth.
* Friends Till The End! is the only non-narrated pill.
* 48 Hour Energy is a reference to the drink 5 Hour Energy.
* X-Lax is a reference to the anti-constipation medicine Ex-Lax.
* "One makes you larger" and "One makes you small" are references to Alice in Wonderland, and the specific wording is a reference to the song White Rabbit by Jefferson Airplane.
* "Percs" is a reference to a street name for the prescription drug Percocet, which is more generically known as Oxycodone. This drug is meant to be used to treat pain, but it is often abused for recreational purposes.
* The "???" is the only pill that has 3 different narrated voice lines.
* "Horse pills" is a slang term used to refer to large, hard to swallow pills, hence their sprites being larger than those of regular pills.

## Gallery

* YouTube - Pills in Repentance - What is New? What Has Changed?
* YouTube - All Horse Pills/Giant Pills (With Sound)
* YouTube - NEW Horse Pills