You need to have mana open so as to be able to play Counterspell
Of course we can also force the transformation when needed with Moonmist and Unnatural Moonrise
While someone could theoretically play several cards in a single turn, her low Willpower makes her a quick target, and the requirement to quest at all is too steep
Creature - Horror Kraken Color tag templates(None) Mocking Doppelganger Flash You may have this creature enter as a copy of a creature an opponent controls, except it has "Other creatures with the same name as this creature are goaded." (They attack each combat if able and attack a player other than you if able.) Creature - Shapeshifter Color tag templates(None) Notion Thief Flash If an opponent would draw a card except the first one they draw in each of their draw steps, instead that player skips that draw and you draw a card
We do lose some flexibility here, but making two copies of a critical Creature for your deck can help you meet your goal
Beginner Box Marvel Super Heroes - Beginner Box If you're new to Magic in general, the Beginner Box is the perfect place to start