Slippery Scoundrel — ruling 1

Once Slippery Scoundrel has become blocked, getting the city’s blessing won’t cause it to become unblocked.

Slippery Scoundrel — ruling 2

Once you have the city’s blessing, you have it for the rest of the game, even if you lose control of some or all of your permanents. The city’s blessing isn’t a permanent itself and can’t be removed by any effect.

Slippery Scoundrel — ruling 3

A permanent is any object on the battlefield, including tokens and lands. Spells and emblems aren’t permanents.

Slippery Scoundrel — ruling 4

If you cast a spell with ascend, you don’t get the city’s blessing until it resolves. Players may respond to that spell by trying to change whether you get the city’s blessing.

Slippery Scoundrel — ruling 5

If you control ten permanents but don’t control a permanent or resolving spell with ascend, you don’t get the city’s blessing. For example, if you control ten permanents, lose control of one, then cast Golden Demise, you won’t have the city’s blessing and the spell will affect creatures you control.

Slippery Scoundrel — ruling 6

If your tenth permanent enters the battlefield and then a permanent leaves the battlefield immediately afterwards (most likely due to the “Legend Rule” or due to being a creature with 0 toughness), you get the city’s blessing before it leaves the battlefield.

Slippery Scoundrel — ruling 7

Ascend on a permanent isn’t a triggered ability and doesn’t use the stack. Players can respond to a spell that will give you your tenth permanent, but they can’t respond to getting the city’s blessing once you control that tenth permanent. This means that if your tenth permanent is a land you play, players can’t respond before you get the city’s blessing.

Slippery Scoundrel — ruling 8

Some cards get power, toughness, and/or abilities once you have the city’s blessing. If another card has an ability that triggers when creatures with certain characteristics enter the battlefield (such as Mentor of the Meek or Elemental Bond do), use the entering permanent’s characteristics after you have the city’s blessing to determine whether those abilities trigger. This is true even if the entering permanent is your tenth permanent.

Slippery Scoundrel : règles, fonctionnement et interactions (MTG)

Slippery Scoundrel 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

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.) As long as you have the city's blessing, this creature has hexproof and can't be blocked.

How it works : Slippery Scoundrel

Original English text — Wizards of the Coast / Scryfall

#1January 19, 2018· Wizards of the Coast
Once Slippery Scoundrel has become blocked, getting the city’s blessing won’t cause it to become unblocked.
No other card is named in this ruling.
#2January 19, 2018· Wizards of the Coast
Once you have the city’s blessing, you have it for the rest of the game, even if you lose control of some or all of your permanents. The city’s blessing isn’t a permanent itself and can’t be removed by any effect.
No other card is named in this ruling.
#3January 19, 2018· Wizards of the Coast
A permanent is any object on the battlefield, including tokens and lands. Spells and emblems aren’t permanents.
No other card is named in this ruling.
#4January 19, 2018· Wizards of the Coast
If you cast a spell with ascend, you don’t get the city’s blessing until it resolves. Players may respond to that spell by trying to change whether you get the city’s blessing.
No other card is named in this ruling.
#5January 19, 2018· Wizards of the Coast
If you control ten permanents but don’t control a permanent or resolving spell with ascend, you don’t get the city’s blessing. For example, if you control ten permanents, lose control of one, then cast Golden Demise, you won’t have the city’s blessing and the spell will affect creatures you control.
No other card is named in this ruling.
#6January 19, 2018· Wizards of the Coast
If your tenth permanent enters the battlefield and then a permanent leaves the battlefield immediately afterwards (most likely due to the “Legend Rule” or due to being a creature with 0 toughness), you get the city’s blessing before it leaves the battlefield.
No other card is named in this ruling.
#7January 19, 2018· Wizards of the Coast
Ascend on a permanent isn’t a triggered ability and doesn’t use the stack. Players can respond to a spell that will give you your tenth permanent, but they can’t respond to getting the city’s blessing once you control that tenth permanent. This means that if your tenth permanent is a land you play, players can’t respond before you get the city’s blessing.
No other card is named in this ruling.
#8January 19, 2018· Wizards of the Coast
Some cards get power, toughness, and/or abilities once you have the city’s blessing. If another card has an ability that triggers when creatures with certain characteristics enter the battlefield (such as Mentor of the Meek or Elemental Bond do), use the entering permanent’s characteristics after you have the city’s blessing to determine whether those abilities trigger. This is true even if the entering permanent is your tenth permanent.
No other card is named in this ruling.