You should also check out our MTG release schedule guide to stay up to date with the latest news, as well as the best MTG Arena decks.
If you want real, official cards to add to your collection or you want them for competitive play, you need some alternatives
Promo - A black star with 'promo' written on it
That's pretty much it - the haste is great for low cost aggressive decks, and drawing cards off dragons is especially good if you can also flicker them
For the low, low cost of one card, you get to attack again, draw a card, and use all of your mana a second time, plus get a crack at additional upkeep/end step triggered abilities and all that good stuff
From there, you can slowly start evolving your Pokemon up with Darkness Grace