Getting behind on the number of cards in your hand is just as bad maybe worse, in fact than getting behind in ink
Shiko and Narset, Unified Shiko and Narset, Unified is a great example of a strong creature with an excellent ability
Marvel ensures you have no maximum hand size, and whenever you cast a spell that targets a creature you control, you draw a card
The cost reduction applies only to generic mana in the cost of creature spells with flying you cast
Auntie Ool, Cursewretch Auntie Ool, Cursewretch is among the narrower options on the list since its card draw is restricted to your ability to put -1/-1 counters on creatures, but that's far from hard
The article from IGN doesnt clarify whether these new cards from the Scene Boxes will be available anywhere else, but it is likely that normal versions of these cards could appear in booster packs of the sets Holiday Release