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They adjust the environment exactly so that they can field test how the players are going to respond to it

This card can be a decent commander for sacrifice decks, but it can also fit right into the 99 of most Rakdos decks

Can I take them out in response to a spell to save my creature (for example, I'm wearing white colored contact lenses and my opponent plays Execute)

B: Syr Cadian, Knight Owl gains flying until end of turn

You can't animate your junkyard or your scrapyard

In fact, as I was going through the list, I did hit a few spots where it felt like making cuts was a bit challenging, which I think is a testament to the improved quality of these recent decks