Gush is one of those odd support cards like Frantic Search that is most abusive in specific combo decks but still has a sufficiently generally useful effect (drawing cards!) that you can play them most places
If a tapped permanent you control has more than one of the subtypes listed in Edward's first ability, count it only once when determining how many Treasure tokens to create
Being able to pay 2 mana to make and sacrifice a creature with no other costs can become very powerful with cards like Grave Pact and the new Martyr's Bond, which unfortunately comes with the Political Puppets deck, not this one
I always like cards that introduce the monarch to the game anyway, but this one provides some solid recursion for a lot of potent cards that people will want to remove
For example, if you don't want to play as Tamatoa, you can easily swap out a villain from the original game or one of the standalone expansions, and see how Davy Jones fairs against Maleficent or King Candy, for example