Welcome, friend! Here are a couple resource to get you started:

What formats are there?

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@ToxiN#02800:

@Loon93#82277:

A Owl makes sense in the context of Theros and Greek Myths. The Owl was a symbol for the Greek Goddess Athena, and a mechanical owl featured prominently in the movie "Clash of the Titans," which was set in Ancient Greece.

It's a flavor win! We now just need Ephara to show up at some point.

The problem isn't the owl. The problem it looks like a kid's toy. Which is absolutely not from the world of minotaurs, hydras and ancient greek creatures. They specifically made it to lure more kids in to play this game, which destroys the whole immersion of a mythological set.
Again, I miss the old phyrexian days.

No, we specifically made it because we think it's adorable.

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MSI link is updated!

https://forums.mtgarena.com/forums/threads/58489

Game Update Highlights

• Theros Beyond Death is now available!
• New Set Mastery and Mastery Pass
  • Click here to learn more about the Theros Beyond Death set mastery.
• New Events: Historic, Traditional Historic, and Brawlers' Guild...

If you're hitting a black screen when you look at packs, restarting your client should correct that. If it doesn't, please report this to our bug forum with game logs so we can look into it as soon as possible.

Roger that, thanks friends. Have you tried launching the game again from the launcher itself?

For those hitting black screen, what operating system are you on?

Also, please please please submit this issue to our bug page with logs. We're looking into it and trying to get things resolved as fast as we can.