Green also has very little access to card draw, most of what it does have has strings attached or is restrictive in some way
Unfortunately, the combo requires you to be in a black and blue colour identity, limiting the decks it can be used in
More details are coming during New York Comicon in October where, as others have noted, theres a Magic and Nickelodeon panel planned
Specifically, you gain an amount of life and draw a number of cards during each of your upkeeps equal to the number of permanents you own controlled by your opponents
Every card is numbered at the very end of its set
If you are a new player who has just purchased one (or both of them), you will find out soon enough that while these decks can be played straight out of the box, they may be limited in what they can do, being "pre-constructed" (which means most opponents will know what to expect)