Astral Cornucopia — ruling 1

If you choose 1 for the value of X, Astral Cornucopia will cost {3} to cast and enter the battlefield with one charge counter. If you choose 2 for the value of X, it will cost {6} to cast and enter the battlefield with two charge counters, and so on.

Astral Cornucopia — ruling 2

The last ability is a mana ability. It doesn't use the stack and can't be responded to.

Astral Cornucopia : règles, fonctionnement et interactions (MTG)

Astral Cornucopia is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

This artifact enters with X charge counters on it. : Choose a color. Add one mana of that color for each charge counter on this artifact.

Complete guide

Astral Cornucopia is a versatile mana rock that scales with your resources, providing a steady stream of colored mana based on how much you invest initially. Whether you need a small boost or a massive mana engine, this artifact adapts to the stage of the game you are currently in.

Scaling Your Investment

The mana cost of Astral Cornucopia is {X}{X}{X}. This means you must pay three mana for every one charge counter you want it to have. For example, if you want it to enter with two charge counters, X is 2, and the total cost will be six mana. If X is 0, it enters with no counters and provides no mana unless you find another way to put counters on it.

How it Resolves

When you cast Astral Cornucopia, you declare the value of X. Once it resolves and enters the battlefield, it arrives with those X counters already on it; this is not a triggered ability, so it doesn't use the stack once it is resolving. The ability to tap for mana is also a mana ability, meaning it happens immediately and your opponents cannot react to you getting the mana.

Choosing Colors

Every time you tap the artifact, you choose a color. You then add one mana of that specific color for every charge counter on it. Note that you cannot split the mana between different colors; if there are three counters, you get three mana of a single chosen color.

Strategic Timing

Early in the game, you might cast this where X=1 just to fix your colors. However, in the late game or in decks that can proliferate counters, Astral Cornucopia becomes a powerhouse that can tap for massive amounts of mana to fuel your biggest spells.

Interaction examples

Fast Starts with Sol Ring

Sol Ring

If you have a Sol Ring on turn one, you can tap it and one land to produce three mana. You can use this to cast Astral Cornucopia with X=1. The artifact enters with one charge counter, allowing you to tap it for one mana of any color starting on turn two.

Late Game Value

In a long game where you have nine mana available, you can cast Astral Cornucopia with X=3. It enters with three charge counters. From then on, each time you tap it, you choose a color and add three mana of that color to your pool.

Equipment Synergy

Skullclamp

If you have an Astral Cornucopia with X=1 and a Skullclamp in hand, you can tap the Cornucopia for one mana of any color (such as colorless or white) and immediately use that mana to pay the Equip cost of Skullclamp. This shows how the Cornucopia acts as a recurring source of utility mana for your other artifacts.

Guide written with AI from the official text and rulings. Official English text prevails.

How it works : Astral Cornucopia

Original English text — Wizards of the Coast / Scryfall

#1February 1, 2014· Wizards of the Coast
If you choose 1 for the value of X, Astral Cornucopia will cost to cast and enter the battlefield with one charge counter. If you choose 2 for the value of X, it will cost to cast and enter the battlefield with two charge counters, and so on.
No other card is named in this ruling.
#2February 1, 2014· Wizards of the Coast
The last ability is a mana ability. It doesn't use the stack and can't be responded to.
No other card is named in this ruling.