In a lot of recent card designs, effects that would previously have triggered at the beginning of your upkeep now trigger at the beginning of your first main phase instead
Jeskai Flashback: If you're playing the Commander 2019 decks straight out of the box, it means that Sevinne, the Chronoclasm is your commander, and I (as well as the community at large, based on our preview rankings) think it's the worst of the face commanders in Commander 2019 by a pretty significant margin
Haste enablers are especially prominent in Goblin decks, which can easily become overwhelming with Krenko, Mob Boss or Krenko, Tin Street Kingpin at the helm
Look closely for incorrect fonts or spelling errors on the cards textofficial Pokmon cards have very high printing standards
Paradox Rift is the English-market relationship
Other TCG collectibles such as the infamous Pikachu Illustrator Pokmon card, were only given out in promotional events