The moon in Terraria moves through a cycle of eight different phases, with the next consecutive phase appearing each night. The current moon phase is indicated by the amount of it that is visible each night. The phase of the moon affects, for instance, the shop inventory of certain NPCs or certain enemy spawn rates.
It takes eight in-game nights for the moon to move through all of its phases. The cycle begins with the full moon upon world creation, where the entire circular moon is visible; and four nights later, after three waning phases, reaches the new moon, where no moon is visible. Another four nights later, after three waxing phases, the cycle ends with the return of the full moon.
Each moon phase starts at dawn (4:30 AM) and lasts until the next dawn. Therefore, a moon phase also encompasses the day preceding the night of that moon phase. This is important because most phase-dependent content and effects are not limited to nighttime.
The following table details items and occurrences that depend on particular moon phases. It refers to both the day and the night of the stated moon phase, unless not applicable or noted otherwise.
- There are nine different styles of the moon: normal, mars-like, saturn-like, mythril style, bright bluish, green, candy, venus-like, and a purple triple moon. When a world is generated, one permanent, random moon style is assigned to it.
- If there is a Frost Moon or a Pumpkin Moon when it is not a full moon, the sprite on the moon will appear in its proper phase, but with the sprite cut to match the size.
- The moon will cycle through phases on the title screen. This is easiest to see by dragging it.
- On the Desktop version and Mobile version, there is a secret 10th "moon" when inputting the seed 05162020. It can only be seen on the Title Screen.
- If the player does not have access to a Sextant, the current moon quarter can be determined by seeing which painting the Painter has for sale, or, in Hardmode, which set of clothes the Clothier has for sale.
- The phases shown suggest that the Terraria map is set on its world's northern hemisphere: The intermediate phases have their circular side on the right for waxing phases, and the left for waning phases.
- Desktop 220.127.116.11: Added several new moon appearances.
- Desktop 18.104.22.168: Added Skeleton Merchant and White Tuxedo set.
- Desktop 1.2.4: Fixed bug where spawn rates would increase underground when a moon event is happening.
- Desktop 1.2: Changed the appearance of the moon, added two extra appearances. All three are chosen at random for a new world.
- Desktop-Release: Introduced.
- Console-Release: Introduced.
- Switch 1.0.711.6: Introduced.
- Mobile-Release: Introduced.
- 3DS-Release: Introduced.
- Information taken from the Desktop 22.214.171.124 source code, function
There may be inaccuracies, as the current Desktop version is 126.96.36.199.
- Only available during the night of the stated moon phase.
- Requires the Angler to be present.
- Requires the Angler to be present, and only in Hardmode.
- Shirt and pants only.
- Available during the night of and day after the stated moon phase.