No matter what you're bouncing with Madam Mim, you ideally have Merlin, Shapeshifter on the board as well, who will gain extra lore value from questing every time a character returns to your hand
I could list every new card I love - like Alice, Growing Girl, who lends the Support keyword to your other characters and gains four lore when you reach ten strength, or Sisu, Divine Water Dragon, who allows you to draw a new card every time you quest - but in general all of the new cards in Rise of the Floodborn feel like a shift in power and ability
Borborygmos is OK to Reanimate into play but is vulnerable to removal and has far less potential effect without attacking
Needing to play a bunch of creatures, needing to wait until your upkeep, and needing to pay two life to draw the card all constrict the power of Call of the Ring just a bit, but for two mana, this can easily fit into all sorts of decks
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