Chorus Infection is the harmful effect that the End content in Legendary Monsters runs on, and you’ll pick it up the first time a Chorusling lands a hit on you. It does damage on its own while the timer runs and keeps moving you a couple of blocks sideways, so a fight you had the spacing on leaves you standing somewhere you didn’t pick.
The damage ignores armor completely, so a full set of Netherite won’t reduce a single point of it. Protection enchantments and Resistance both still count against it, so they’re the only gear that does anything until you can craft the 
Chorus Mask.
Obtaining
Every source of it sits in the End, either on the two mobs from the Ancient Tower Remains or on the items you make out of their drops. Choruslings apply it in melee, the Chorusent applies it with its sweeping attacks, and there’s an 
Infected Chorus Fruit that gives it to you if you eat it.
| Source | Duration | Applies |
|---|---|---|
| Chorusling melee hit | 3 seconds | Every hit that isn’t blocked |
| Chorusent sweep attacks | 2 seconds | Half its swings, if you’re not blocking |
| Infected Chorus Fruit, eaten | 8 seconds | Always |
| Chorus Bomb from the Chorus Cannon | 4 seconds | Everything within 3.5 blocks of the blast |
Choruslings spawn on their own across the main End islands, so you don’t have to find the tower to meet the effect. They come one at a time rather than in groups, so the first dose usually arrives while you’re crossing terrain rather than in a fight you went looking for.
You’ll find the tower with an 
Eye Of Chorus, which is 4 
Chorus Fruit around an 
Ender Pearl, thrown and followed like an Eye of Ender. It usually drops back to be picked up, but about 1 throw in 5 shatters it, so craft a couple before you set off.
The Ancient Tower Remains is where it comes at you properly, as the structure is built with three Chorusling spawners around the Chorusent. The tower only generates in End Highlands and End Midlands, not on the Small End Islands the Choruslings wander, so you’ll need to be out past a Gateway.
Infection Ingredients
Killing Choruslings is the only way to get the Infected Chorus Fruit, which is the ingredient in all three Chorus items as well as being food. The 
Chorus Crystal that finishes those same three recipes only drops from the Chorusent, and you’re given one every time you beat it.
It restores 5 hunger and infects you for 8 seconds with no chance of avoiding it, which averages out at around 24 damage straight through your armor. Save the stack for crafting and eat something else.
Both drops also go into the Chorus Mask, which is the cure covered further down the page. Until you have one, treat the fruit as a crafting material and nothing else, however hungry you get out on the islands.
Effects
While the effect is on you it keeps rolling in the background and lands about once a second. Each time it fires you take 3 damage and get teleported, and both halves happen together, so there’s no reading the damage as a warning that the teleport is coming.
The teleport drops you within about 2 blocks of where you were, at the same height, onto a block with room to stand. It won’t throw you into the void, though it will pull you out of the corner you held. If it can’t find a spot in a few attempts it leaves you put, so on a narrow bridge you’ll mostly just take the damage.
The level of the effect doesn’t change any of this. The Chorusent applies it at level III and the 
Chorus Cannon applies it at level I, and they behave identically, the only thing that differs between sources is how long the timer runs. Doses don’t add together either, a new hit just refreshes the timer when it’s longer than what’s left on you.
Using It Against Mobs
Mobs take Chorus Infection exactly the way you do, teleports included, and the Chorus Cannon is the one item that puts it on them. The 
Chorus Blade is built out of the same drops, an 
Iron Sword with a Chorus Crystal and 2 Infected Chorus Fruit, but it gives you a right-click teleport of up to 5 blocks instead, on a 1 second cooldown.
The Chorus Cannon is the heavier option and is built on the 
Sand Cannon you craft from Ruined Pyramid drops. It fires a Chorus Bomb after about three quarters of a second of charge. A direct hit does 8, then the blast infects everything within 3.5 blocks for 4 seconds, on a 6.5 second cooldown. It repairs with Infected Chorus Fruit, so the Choruslings you farm keep it fed.
The bomb doesn’t care who threw it, and everything caught in that 3.5 block radius gets infected including you. Firing it at something already in melee range is a good way to hand yourself 4 seconds of the effect, so it’s better used on a Chorusling that’s still walking in.
Curing and Preventing It
The Chorus Mask is the proper answer, as it strips Chorus Infection off you every tick while it’s on your head. The effect still gets applied by the mobs, it’s simply removed again before it’s able to roll for damage, so you can stand in a Chorusling‘s swings and the infection never lands.
As a Helmet it’s worth 3 armor points with 242 durability, and it repairs with ordinary Chorus Fruit, which grows everywhere you’d be wearing it anyway. The catch is the Chorus Crystal in the recipe, that only drops from the Chorusent, so you can’t wear the mask into the tower the first time.
Until you’ve beaten the boss once, a 
Milk Bucket is what you take instead. It clears the effect the same as any other, though it clears your Strength and Resistance with it, so it’s worth carrying two or three and drinking between waves rather than mid-swing.
Tips
Blocking prevents the effect outright, as neither the Chorusling nor the Chorusent will apply it to a target that’s holding a 
Shield up. Those same attacks disable your Shield for 2 seconds when they connect though, so the next swing is the one that infects you. Treat the Shield as a way to skip one dose, not all of them.
Fight near the middle of an island where you can. The teleport won’t put you anywhere without ground under it, but it will happily move you 2 blocks closer to a Chorusling that was about to be out of reach, and those swing at anything within 3.5 blocks. That’s worse on a thin strip of 
End Stone than it is in open space.
Bring an 
Elytra by the time you’re hunting for the Ancient Tower Remains, as the towers generate about 65 chunks apart. Choruslings spawn along the way as well, so you’re likely to pick up your first dose of the infection while you’re still crossing the gap, rather than after you’ve already landed.
Break the three Chorusling spawners in the Ancient Tower Remains before you wake the Chorusent up, since Chorusling infections land on every hit while the boss only manages it on half its sweeps. Doing it the other way around means the timer is being topped up from both sides and you’re taking 3 damage a second through your armor while trying to read a boss.
FAQ
It rolls in the background while the timer runs and fires about once a second, dealing 3 damage and teleporting you up to 2 blocks at the same time. The damage is magic, so armor points do nothing against it, and the teleport only lands you somewhere with solid ground beneath your feet.
Drinking a Milk Bucket clears it like any other effect, and it’s the only cure you have before the Chorusent dies. After that the Chorus Mask handles it for you, as wearing it removes the infection every tick, so it never gets a roll in.
Blocking does stop it being applied, since both the Chorusling and the Chorusent skip the effect on a target that’s blocking. They also disable your Shield for 2 seconds on the same hit though, so the follow-up swing gets through and infects you anyway.
The amplifier is ignored, so the level III the Chorusent puts on you does the same 3 damage a second as the level I from a Chorus Bomb. Duration is the only thing that separates the sources, running from 2 seconds on a Chorusent sweep up to 8 seconds from the fruit.
