Complete specific Missions to unlock and these characters
Probably the most competitive examples would be similar to the infinite life Kitchen Finks combo, which currently uses Anafenza, Kin-Tree Spirit or Melira, Sylvok Outcast
Madam Mim in particular can be trickier for new players, requiring the player to banish one of their own cards to bring out the shapeshifting witch - if you dont plan ahead, you might end up discarding one of the cards you needed
Patriars Seal works quite nicely as well, and Minamo, School at Waters Edge is in the color identity
When you draw a card, ask yourself: Is this card more useful in play, saving it, or adding it to my Inkwell? Whereas, if you only have 11 copies of cards that cost 5 or more, such as Mad Hatter Gracious Host , Dragon Fire , and Rapunzel Letting Her Hair Down (decklist), you can pump the brakes on your Inkwell around 4 and ease into having 5 or 6