Astrology

This page is out of date (v1.0.3).

Astrology

This article is about the Astrology skill. For training the skill, see Astrology/Training.

Astrology is a skill that provides passive buffs to various other skills in the game similar to the Agility skill. Modifiers will be unlocked as you level up your mastery in each constellation, and can be re-rolled by spending Stardust or Golden Stardust.

Mechanics

Acquiring Stardust

Both Stardust and Golden Stardust are exclusively obtained from Astrology. Both are acquired at random while studying constellations, where Stardust and Golden Stardust drops with a 1% and 0.20% chance per action respectively.

The rate at which stardust may be acquired can be increased by:

• Decreasing the action interval - The Secret Stardust Potion reduces the action interval by 3/5/10/15% depending on the potion's tier. Note that since the potions themselves use Stardust as an ingredient, maximising the Herblore preservation and doubling chances before creating any of these potions is highly recommended.
• Increasing the drop chance
  • For Stardust, the 25% Mastery pool checkpoint provides a +1% bonus to the drop chance, for a maximum chance of 2%.
  • For Golden Stardust, the 50% Mastery pool checkpoint provides a +0.2% bonus, and Astro provides a +0.1% bonus to the drop chance, for a maximum chance of 0.5%.
• Increasing the drop quantity - Equipping the Astrology Skillcape provides a +1 bonus to the quantity of both Stardust and Golden Stardust that is dropped.

Modifiers

When unlocked, each constellation will initially have a single standard modifier star unlocked. Increasing the Mastery level of a constellation will unlock additional stars (and therefore additional modifiers), up to a maximum of 3 standard modifiers and 3 unique modifiers per constellation.

Each modifier will start with a random modifier and value out of the possible modifiers available for that constellation, where the list of possible modifiers for a constellation can be viewed either within the constellations table or in-game by clicking Explore followed by View Possible Modifiers on the constellation.

Rerolling Modifiers

Modifiers can be re-rolled in order to change both the modifier its self and value of the modifier. Re-rolling standard modifiers costs Stardust, while re-rolling unique modifiers costs Golden Stardust. The cost of re-rolling always applies and cannot be avoided with preservation chance modifiers. For any constellation, re-rolling may be performed for all standard or unique modifiers at the same time at a cost of 1 stardust per roll, or individually at the cost of 30 stardust per roll. The cost of re-rolling modifiers individually may be halved to 15 stardust when the player reaches the 95% Mastery pool checkpoint.

When rolled, the value of each modifier is a random whole number between 1 and 5 inclusive, with larger values being less common than lower values. The chance of rolling each value can be found in the Reroll Chances section of this page.

Due to the low chance of rolling a modifier with a value of 5 re-rolling all modifiers until each has the maximum value of 5 is discouraged, as doing so would require a significant amount of both Stardust and Golden Stardust. Instead, consider the following strategy:

1. Decide on a minimum acceptable value (say 3% or 4%).
2. Re-roll all standard or unique modifiers until at least one of the modifiers is one that is desirable to the player with at least minimum acceptable value.
3. Individually re-roll the other standard or unique modifiers until they also become modifiers that the player desires with the minimum acceptable value. Ideally, individual re-rolling should only occur after the 95% Mastery pool checkpoint has been reached due to the significant stardust saving this will bring.

Mastery Unlocks

Item Mastery Unlocks

Level	Unlock
20	Unlock another Star (Unique Modifier)
40	Unlock another Star (Standard Modifier)
60	Unlock another Star (Unique Modifier)
80	Unlock another Star (Standard Modifier)
99	Unlock another Star (Unique Modifier)

Mastery Pool Checkpoints

Pool %	Pool XP	Bonus
10%	550,000 xp	+5% increased Astrology Mastery XP
25%	1,375,000 xp	+1% chance to find Stardust
50%	2,750,000 xp	+0.2% chance to find Golden Stardust
95%	5,225,000 xp	-50% Cost to reroll specific Modifiers
Total Mastery Pool XP		5,500,000

Skillcape

The skillcape can be purchased from the store for  1,000,000 after the player reaches Level 99.

Skillcape	Name	Effect
	Astrology Skillcape	+1 to base drop quantity of Stardust and Golden Stardust from Astrology.

Pet

The pet can be unlocked by doing any Astrology action.

Pet	Name	Effect
	Astro	+0.1% chance to find Golden Stardust

Constellations

The bonuses listed below are the maximum possible. The actual value will between 1 and 5. The chance of each result can be found in the Reroll Chances section of this page.

Constellation		Level	XP	Skills	Standard Modifiers	Unique Modifiers
	Deedree	1	5	Woodcutting Farming	+5% Woodcutting Skill XP +5% Chance to Double Items in Woodcutting +5% Woodcutting Mastery XP +5% Farming Skill XP +5% Chance to Double Items in Farming +5% Farming Mastery XP	+5% Bird Nest drop rate +5% Farming Yield
	Iridan	10	13	Attack Smithing	+5% Attack Skill XP +5 Hidden Attack Level +5% GP From Monsters +5% Global Accuracy +5% Smithing Skill XP +5% Chance to Double Items in Smithing +5% Smithing Mastery XP	+5% of Maximum Hit added to Minimum Hit -5% Smithing Interval
	Ameria	20	21	Fishing Firemaking	+5% Fishing Skill XP +5% Chance to Double Items in Fishing +5% Fishing Mastery XP +5% Firemaking Skill XP +5% Chance to Double Items in Firemaking +5% Firemaking Mastery XP	+5% chance to receive Special Items from Fishing -5% Fishing Interval +5% chance to receive a Diamond per action in Firemaking (Cannot be doubled) -5% Firemaking Interval
	Terra	30	29	Strength Mining	+5% Strength Skill XP +5 Hidden Strength Level +5% GP From Monsters +5% Global Accuracy +5% Mining Skill XP +5% Chance to Double Items in Mining +5% Mining Mastery XP	+5% Melee Strength Bonus from Equipment +5 Mining Node HP +5% chance to do zero damage to Ores and Rune Essence +5% Chance to receive gems from Mining (Does not work for Rune Essence)
	Vale	40	37	Hitpoints Cooking	+5% Hitpoints Skill XP +5% GP From Monsters +5% Global Accuracy +5% Cooking Skill XP +5% Chance to Double Items in Cooking +5% Cooking Mastery XP	+5% Hitpoint Regeneration +5% Lifesteal +5% Food Healing Value +5% chance to Preserve Food when eaten -5% Cooking Interval
	Syllia	50	45	Ranged Fletching	+5% Ranged Skill XP +5 Hidden Ranged Level +5% GP From Monsters +5% Global Accuracy +5% Fletching Skill XP +5% Chance to Double Items in Fletching +5% Fletching Mastery XP	+5% Ranged Strength Bonus from Equipment +5 Ranged Accuracy Bonus +5% Ammo Preservation
	Arachi	60	53	Magic Runecrafting	+5% Magic Skill XP +5 Hidden Magic Level +5% GP From Monsters +5% Global Accuracy +5% Runecrafting Skill XP +5% Chance to Double Items in Runecrafting +5% Runecrafting Mastery XP	+5% Magic Damage Bonus from Equipment +5% Magic Accuracy Bonus +5% Rune Preservation for Alt. Magic Spells +5% chance to receive random elemental runes per Runecraft
	Ko	70	61	Agility Thieving	+5% Agility Skill XP -5% Agility Obstacle Build Costs +5% Agility Mastery XP +5% Thieving Skill XP +5% Chance to Double Items in Thieving +5% Thieving Mastery XP	+5% GP From Agility +5% minimum GP from Thieving
	Tellus	80	69	Defence Slayer	+5% Defence Skill XP +5 Hidden Defence Level +5% GP From Monsters +5% Global Accuracy +5% Slayer Skill XP +5% Slayer Coins +5% GP From Monsters +5% Global Accuracy	+5% increased Evasion Ratings +5% Reflect Damage +5% Damage To Slayer Tasks +5% Damage To Slayer Area Monsters
	Hyden	90	77	Prayer Crafting	+5% Prayer Skill XP +5% GP From Monsters +5% Global Accuracy +5% Crafting Skill XP +5% Chance to Double Items in Crafting +5% Crafting Mastery XP	+5% Chance To Preserve Prayer Points -5% Crafting Interval +5% chance to double when creating Leather, Hard Leather or Dragonhide Armour in Crafting.
	Qimican	95	85	Summoning Herblore	+5% Summoning Skill XP +5% Chance to Double Items in Summoning +5% Summoning Mastery XP +5% Herblore Skill XP +5% Chance to Double Items in Herblore +5% Herblore Mastery XP	+5% Chance to preserve Summoning Charges -5% Summoning Interval +5% Chance To Preserve Potion Charge -5% Herblore Interval

Reroll Chances

Whenever a bonus from a Constellation is rolled or re-rolled, the value of the bonus will be between 1 and 5. The odds of rolling each value are listed below:

Value	Chance
	This Value	This Value or Greater
1	50%	100%
2	30%	50%
3	15%	20%
4	4%	5%
5	1%	1%

Potion

The Secret Stardust Potion reduces the interval for Study actions.

Potion	Tier	Charges	Effect
	I	5	-3% Astrology Interval
	II	10	-5% Astrology Interval
	III	15	-10% Astrology Interval
	IV	25	-15% Astrology Interval

Skill Boosts

This table lists most sources of Astrology-specific modifier boosts. For a list of boosts that apply to all skills, see the Skill Boosts page. This list does not contain boosts provided from Mastery rewards.

Source	Type	Astrology Boosts	Other Modifiers
Secret Stardust Potion I	Item	-3% Astrology Interval
Secret Stardust Potion II	Item	-5% Astrology Interval
Secret Stardust Potion III	Item	-10% Astrology Interval
Secret Stardust Potion IV	Item	-15% Astrology Interval
Ancient Ring of Skills	Item (Ring)	+8% Astrology Skill XP	+8% Alt. Magic Skill XP +8% Woodcutting Skill XP +8% Fishing Skill XP +8% Firemaking Skill XP +8% Cooking Skill XP +8% Mining Skill XP +8% Smithing Skill XP +8% Farming Skill XP +8% Thieving Skill XP +8% Fletching Skill XP +8% Crafting Skill XP +8% Runecrafting Skill XP +8% Herblore Skill XP +8% Agility Skill XP +8% Summoning Skill XP

Melvor Idle version v1.0.4 (Released: 25th May 2022)
Combat: Attack Strength Defence Hitpoints Ranged Magic Prayer Slayer
Skills: Woodcutting Fishing Firemaking Cooking Mining Smithing Thieving Farming Fletching Crafting Runecrafting Herblore Agility Summoning Astrology Alternative Magic
Other: Beginners Guide Guides Bank Combat Mastery Money Making Shop Easter Eggs Pets Golbin Raid
Reference Tables: Items, Equipment, Experience Table, Upgrading Items, Dungeons, Chest Loot Tables, Monsters, Monster Loot Tables