Of those original 21, these nine learn cards are all within the Standard playable range
[34] The rarities listed in increasing rarity are: Common (gray circle) Uncommon (white book) Rare (bronze triangle) Super Rare (silver diamond) Legendary (gold pentagon) Epic (rainbow semicircle with nib) Enchanted (rainbow hexagon) Iconic (rainbow octagon) The Epic and Iconic rarity were introduced in the Fabled set
This reminds me of Kona, Rescue Beastie in terms of the risk/reward involved, but a little bit weaker overall
These spells can be useful to incorporate into your deck as long as the enchantment or artifact fits the overall theme of your deck
It's not like there's an archetype that relies on low-cost, low-to-the-ground creatures to win games swiftly, right
By swapping a situational removal piece for a permanent growth engine, you ensure that every Mutagen token provides double the value