A question has been raised in a Japanese forum about Tezzeret, Cruel Machinist.

Core 2019 Release notes says:

The Core Set 2019 set includes no way to turn these cards face up. If an effect from cards outside of this set does turn one face up, the effect causing it to be a 5/5 artifact creature ends. If such an effect tries to turn an instant or sorcery card face up, reveal that card and it stays face down. In that case, it remains a 5/5 artifact creature.

Some judges want to know the mechanism why the animate efffect ends when those objects turn face up. And I think that the animate effect doesn't end according to rules quoted below.

707.8 Any effects that have been applied to the face-down permanent still apply to the face-up permanent.

611.2e If a resolving spell or ability both puts a nontoken permanent onto the battlefield and creates a continuous effect stating that the permanent “is ［characteristic］,” that continuous effect applies simultaneously with the permanent entering the battlefield.

I think Tezzeret's ultimate ability is an “is ［characteristic］” effect, and since it is an effect, CR707.8 will be aplied to it.

Am I wrong or are there any rule changes at Core 2019 release?

Edited Takeshi Sue (June 26, 2018 08:27:29 AM)

The Release Notes are correct. A card put onto the battlefield with Tezzeret, Cruel Machinist's ultimate is a 5/5 artifact creature in the same way and for the same reasons that a card manifested or played with the Morph ability is a 2/2 creature: those are the characteristics defined by the ability (in this case, Tezzeret's) that causes them to be face-down. It is not a separate animation effect independent from their face-down status–being face-down is what makes them 5/5 artifact creatures, so when they stop being face-down, they stop being 5/5 artifact creatures.

In general, while a set's release notes may contain snippets of text that will appear in the associated update to the Comprehensive Rules, especially rules detailing new keywords, they do not contain a full listing of rules that will be changing, because that's not what they're for. It's very common for a set's release notes to contain information that is not supported by previous editions of the CR, such as the Core 2019 Release Notes listing ‘Vivien’ as a subtype in the oracle text for Vivien of the Arkbow when ‘Vivien’ is not listed in the June 8th release of the CR as a valid planeswalker type.

In such cases, it's generally a safe assumption that the Comprehensive Rules will be changing with the next release to support the information contained in the release notes.

Edited Callum Milne (June 26, 2018 12:55:35 PM)