Artisan of Forms — ruling 1

You choose the target for the triggered ability when the ability is put onto the stack. You choose whether or not Artisan of Forms becomes a copy of that creature when the ability resolves.

Artisan of Forms — ruling 2

Artisan of Forms copies the printed values of the creature plus any copy effects that have been applied to it. It won't copy any other effects that have changed that creature's power, toughness, color, and so on. Artisan of Forms won't copy any counters on the creature, but Artisan of Forms will retain any counters it already had on it.

Artisan of Forms — ruling 3

If Artisan of Forms becomes a copy of a token creature, it copies the original characteristics of that token as defined by the effect that put it onto the battlefield. It won't become a token creature.

Artisan of Forms — ruling 4

The copy effect lasts indefinitely. Often, it will last until it is overwritten by another copy effect (if it copies another creature on a future turn, perhaps).

Artisan of Forms — ruling 5

If the creature is an illegal target when the ability tries to resolve, the ability won't resolve. Artisan of Forms won't become a copy of that creature. It remains whatever it was a copy of.

Artisan of Forms — ruling 6

When Artisan of Forms becomes a copy of a creature, it's neither entering nor leaving the battlefield. Any enters-the-battlefield or leaves-the-battlefield abilities won't trigger.

Artisan of Forms — ruling 7

If another creature becomes a copy of Artisan of Forms, it will become a copy of whatever Artisan of Forms is currently copying (if anything), plus it will have the triggered ability.

Artisan of Forms — ruling 8

Heroic abilities will resolve before the spell that caused them to trigger.

Artisan of Forms : règles, fonctionnement et interactions (MTG)

Artisan of Forms 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

Heroic — Whenever you cast a spell that targets this creature, you may have this creature become a copy of target creature, except it has this ability.

How it works : Artisan of Forms

Original English text — Wizards of the Coast / Scryfall

#1September 15, 2013· Wizards of the Coast
You choose the target for the triggered ability when the ability is put onto the stack. You choose whether or not Artisan of Forms becomes a copy of that creature when the ability resolves.
No other card is named in this ruling.
#2September 15, 2013· Wizards of the Coast
Artisan of Forms copies the printed values of the creature plus any copy effects that have been applied to it. It won't copy any other effects that have changed that creature's power, toughness, color, and so on. Artisan of Forms won't copy any counters on the creature, but Artisan of Forms will retain any counters it already had on it.
No other card is named in this ruling.
#3September 15, 2013· Wizards of the Coast
If Artisan of Forms becomes a copy of a token creature, it copies the original characteristics of that token as defined by the effect that put it onto the battlefield. It won't become a token creature.
No other card is named in this ruling.
#4September 15, 2013· Wizards of the Coast
The copy effect lasts indefinitely. Often, it will last until it is overwritten by another copy effect (if it copies another creature on a future turn, perhaps).
No other card is named in this ruling.
#5September 15, 2013· Wizards of the Coast
If the creature is an illegal target when the ability tries to resolve, the ability won't resolve. Artisan of Forms won't become a copy of that creature. It remains whatever it was a copy of.
No other card is named in this ruling.
#6September 15, 2013· Wizards of the Coast
When Artisan of Forms becomes a copy of a creature, it's neither entering nor leaving the battlefield. Any enters-the-battlefield or leaves-the-battlefield abilities won't trigger.
No other card is named in this ruling.
#7September 15, 2013· Wizards of the Coast
If another creature becomes a copy of Artisan of Forms, it will become a copy of whatever Artisan of Forms is currently copying (if anything), plus it will have the triggered ability.
No other card is named in this ruling.
#8September 15, 2013· Wizards of the Coast
Heroic abilities will resolve before the spell that caused them to trigger.
No other card is named in this ruling.
#9September 15, 2013· Wizards of the Coast
Heroic abilities will trigger only once per spell, even if that spell targets the creature with the heroic ability multiple times.
No other card is named in this ruling.
#10September 15, 2013· Wizards of the Coast
Heroic abilities won't trigger when a copy of a spell is created on the stack or when a spell's targets are changed to include a creature with a heroic ability.
No other card is named in this ruling.