Volrath, the Shapestealer — ruling 1

Activating Volrath's last ability causes it to lose its first ability until your next turn, so if you activate it before the beginning of combat step, it won't trigger during that turn. Players can cast instant spells and activate abilities (such as the second ability) during the beginning of combat step after that first ability has triggered or resolved but before attackers are chosen in the declare attackers step.

Volrath, the Shapestealer — ruling 2

If a creature has +1/+1 counters and -1/-1 counters on it, state-based actions remove the same number of each so that it has only one of those kinds of counters on it. This may cause the creature to no longer have any counters on it.

Volrath, the Shapestealer — ruling 3

Volrath copies the printed values of the target creature, plus any copy effects that have been applied to it. It won't copy counters on that creature. It also won't copy any effects that have changed its power, toughness, types, color, or so on. Notably, it won't copy effects that made the target become a creature if it's not normally a creature.

Volrath, the Shapestealer — ruling 4

If Volrath becomes a copy of a face-down creature, Volrath becomes a 7/5 creature with no color, cost, or creature type. Volrath is still face up.

Volrath, the Shapestealer — ruling 5

If Volrath copies a creature that's copying something else, it will become whatever the target is copying.

Volrath, the Shapestealer — ruling 6

If the target creature is a token, Volrath copies the original characteristics of that token as stated by the effect that created the token. Volrath doesn't become a token in this case.

Volrath, the Shapestealer — ruling 7

If an effect begins to apply to Volrath before it becomes a copy of another creature, that effect will continue to apply.

Volrath, the Shapestealer — ruling 8

If Volrath copies a creature the same turn Volrath enters the battlefield, you can't attack with it or use any of its {T} abilities (if it gains any) unless the copied creature has haste.

Volrath, the Shapestealer : règles, fonctionnement et interactions (MTG)

Volrath, the Shapestealer 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

At the beginning of combat on your turn, put a -1/-1 counter on up to one target creature. : Until your next turn, Volrath becomes a copy of target creature with a counter on it, except it's 7/5 and it has this ability.

How it works : Volrath, the Shapestealer

Original English text — Wizards of the Coast / Scryfall

#1August 23, 2019· Wizards of the Coast
Activating Volrath's last ability causes it to lose its first ability until your next turn, so if you activate it before the beginning of combat step, it won't trigger during that turn. Players can cast instant spells and activate abilities (such as the second ability) during the beginning of combat step after that first ability has triggered or resolved but before attackers are chosen in the declare attackers step.
No other card is named in this ruling.
#2August 23, 2019· Wizards of the Coast
If a creature has +1/+1 counters and -1/-1 counters on it, state-based actions remove the same number of each so that it has only one of those kinds of counters on it. This may cause the creature to no longer have any counters on it.
No other card is named in this ruling.
#3August 23, 2019· Wizards of the Coast
Volrath copies the printed values of the target creature, plus any copy effects that have been applied to it. It won't copy counters on that creature. It also won't copy any effects that have changed its power, toughness, types, color, or so on. Notably, it won't copy effects that made the target become a creature if it's not normally a creature.
No other card is named in this ruling.
#4August 23, 2019· Wizards of the Coast
If Volrath becomes a copy of a face-down creature, Volrath becomes a 7/5 creature with no color, cost, or creature type. Volrath is still face up.
No other card is named in this ruling.
#5August 23, 2019· Wizards of the Coast
If Volrath copies a creature that's copying something else, it will become whatever the target is copying.
No other card is named in this ruling.
#6August 23, 2019· Wizards of the Coast
If the target creature is a token, Volrath copies the original characteristics of that token as stated by the effect that created the token. Volrath doesn't become a token in this case.
No other card is named in this ruling.
#7August 23, 2019· Wizards of the Coast
If an effect begins to apply to Volrath before it becomes a copy of another creature, that effect will continue to apply.
No other card is named in this ruling.
#8August 23, 2019· Wizards of the Coast
If Volrath copies a creature the same turn Volrath enters the battlefield, you can't attack with it or use any of its abilities (if it gains any) unless the copied creature has haste.
No other card is named in this ruling.
#9August 23, 2019· Wizards of the Coast
If Volrath becomes a copy of a legendary creature you control, you'll put one of them into your graveyard.
No other card is named in this ruling.
#10August 23, 2019· Wizards of the Coast
If another object becomes a copy of Volrath, it has the ability to become a copy of something else and it's 7/5.
No other card is named in this ruling.
#11August 23, 2019· Wizards of the Coast
If Volrath becomes a copy of a creature whose power and toughness are defined by an ability (usually printed as */* or similar), Volrath doesn't copy the ability that defines its power and toughness. Volrath remains a 7/5 creature.
No other card is named in this ruling.
#12August 23, 2019· Wizards of the Coast
If Volrath copies a creature with an ability that can be activated only once each turn (such as Chainer, Nightmare Adept), you can activate that ability once. If Volrath then becomes a copy of that same creature, you can activate that ability another time, and so on.
No other card is named in this ruling.