This is downright nasty in decks with newly unblockable Commanders led by Rogue's Passage and Sun Quan or with unblockable or evasion themselves (Dromar, the Banisher
Sorin, Imperious Bloodlord Sorin, Imperious Bloodlord saw a lot of play in Pioneer as a way to cheat massive vampires into play, like Champion of Dusk and Vein Ripper, so much so that it ended up banned in the format
Elsa, Spirit of Winter is a powerful top end card for Amethyst decks
However, Ralph is definitely a popular character, and his card (or at least the Enchanted version of it!) placing so highly on the list of the most wanted Azurite Sea cards is a testament to that
You can jump it in during an opponents turn and recast a counterspell or a removal spell from your yard
Since it's a song, it can be sung by any character with a cost of 3 or more or any character with Singer 3 or more