For the blue stars that give the player mana when collected, see Star.
A star falling from the sky.
The Fallen Star is an item that randomly falls from the sky at night and disappears at dawn (4:30 AM). They can be used to craft Mana Crystals, which permanently increase a player's mana capacity by 20 points each. They are also used in a variety of crafting recipes, and as ammunition for the Star Cannon and Super Star Shooter(Desktop, Console and Mobile versions). Hence, Fallen Stars can be stored in ammo slots.
Fallen Stars will spawn randomly throughout the entire nighttime, and their spawn rate is determined by two factors: the world size and a multiplier randomly set at nightfall. See Notes for details.
Fallen Stars emit light while on the ground, making them easy to spot at night. They cannot be placed by the player as permanent light sources, but can be combined with a Bottle to craft the Star in a Bottle. They will disappear during the day, regardless of whether they are dropped by a player, but can remain in a player's inventory or a storage item (such as a Chest) indefinitely.
In the uncommon event that a Fallen Star hits an enemy or critter, it will deal 1000 base damage to the struck entity.[1] Fallen Stars cannot damage players, unless playing in a Don't dig up(Desktop, Console and Mobile versions) or Get fixed boi(Desktop, Console and Mobile versions) world. In these worlds, Fallen Stars that fall from the sky do not drop as an item on impact, and can only be obtained from slimes as their bonus drop.
The default Fallen Star multiplier is 1. Each night, the multiplier will be randomly increased. There is a 1/10 (10%) chance (1/5 (20%) chance in Celebrationmk10(Desktop, Console and Mobile versions) worlds) for a Meteor Shower to be started, and a random value between 300 and 500 (inclusive) is chosen. If this failed, then there is a 1/3 (33.33%) chance (1/2 (50%) chance in Celebrationmk10 worlds) for a random value between 100 and 150 (inclusive) to be chosen. The multiplier is then set to 0.01 × chosen value.[2]
This equals a 200%–400% increase during Meteor Showers, and a 0%–50% increase during regular nights.
Then, the spawn of Fallen Stars will be determined each game tick[3]. The game will use the total width of the world (maxTilesX) and the above multiplier to determine the spawn chance. The formula is:[4]
When the multiplier is 1, the spawn chance per tick is 1/800 (0.13%) for small worlds, 3/1600 (0.19%) for medium worlds, and 1/400 (0.25%) for large worlds.
Therefore, the average number of Fallen Stars per night (when the multiplier is 1) is 40.5 in a small world, about 61.71 in a medium world, and 81 in a large world.
Fallen Stars spawn anywhere within the upper 5% of the world, i.e. 60 tiles in small worlds, 90 tiles in medium worlds, and 120 tiles in large worlds.
Moon phase and lateral map position have no effect on the frequency of Fallen Stars. Their appearance is at a fixed rate at all hours of every night.
Unlike most items collected as drops, Fallen Stars fall all over the world at night, even in areas far from the player.
If an enemy is killed by a Fallen Star, the kill will be attributed to the player; the Tally Counter(Desktop, Console and Mobile versions) will update to reflect the kill, and banners will be dropped accordingly. When multiple players are present, the kill and banner will be given to the host of the world.
This can cause the Empress of Light(Desktop, Console and Mobile versions) to spawn if a Prismatic Lacewing(Desktop, Console and Mobile versions) (which also spawns at night) was hit.
Fallen Stars will not fall while time is frozen in Journey Mode(Desktop, Console and Mobile versions).
Tips
On the Desktop version, Console version, and Mobile version, sleeping in a Bed will fast-forward time, which increases the rate at which stars fall relative to real-world time. This can be exploited to quickly gather stars, by sleeping for most of the night then collecting accumulated stars near the end. This also applies to Journey Mode's time acceleration which at 10× allows for very quick Fallen Star farming.
Traveling a far distance a few minutes prior to dawn will allow the player to collect the Fallen Stars, easily netting a large supply.
A simple method for harvesting Fallen Stars is to construct long straight sections of ground to run along at night; a skybridge also works well. Note that diagonal platforms may not intercept Fallen Stars. When constructing a large skybridge, the platform to catch them should be placed at the bottom of Space.
To pass Fallen Stars to another player during daytime, transfer it using a storage item, e.g. a Chest, since throwing it out of the inventory during the day will make it vanish.
If the player's inventory is full, Fallen Stars can be moved to an empty ammo slot to free up an inventory slot.
Fallen Stars will hit Floating Islands if the island is in the path of the star, so if there is an area where Fallen Stars never seem to fall or rarely do, there is a possibility that a Floating Island is above that area.
Trivia
If "used" via ⚒ Use / Attack, the player will hold the star above their head and a sound will play, similarly to the Mana Crystal. However, unlike the Mana Crystal, it will neither be consumed nor have any effect on the player. This effect is left over from before 1.1, when Fallen Stars were used to restore mana.
The star will, if in semi-darkness, seem to be as bright as if it was shown in the day, but will not produce any light around it, similar to the Angel Halo.
There is a projectile related with the spawning of Fallen Stars, with the ID 720.[1] Technically, when a Fallen Star is going to be spawned, this projectile is spawned first, then it creates a Fallen Star projectile.
See also
Fallen Starfish, a quest fish said to be a Fallen Star that became a fish.
↑ 1.01.1Information taken from the Desktop1.4.4.9 source code, method AI_148_StarSpawner() in Terraria.Projectile.cs.
↑Information taken from the Desktop1.4.4.9 source code, method NightSetup() in Terraria.Star.cs.
↑A tick is a time unit countable by the software. Most of Terraria's updating logic happens every tick. A tick has the length of 1/60th of a second, hence there are 60 ticks in a second and 3600 ticks in a minute.
↑Information taken from the Desktop1.4.4.9 source code, method UpdateWorld() in Terraria.WorldGen.cs.