Of these three, I think Wrath of the Skies is the most impressive, though
This blue creature finds a natural home in mill decks and works as a janky recursion spell, like a Rise from the Grave that works with creature synergies like Animar, Soul of Elements
True rarity (limited prints) outpaces short-term meta cards
However, 'Grass' decks often have developments where 'That Grass Looks Greener' resolves, creating a large resource gap and allowing you to play the game, which can cover for some mistakes and lead to a win
Kaervek can target multicolored cards in your graveyard, so long as they're at least black in addition to their other colors
Taking a near-guaranteed loss against Zekrom, Reshiram, or any other post-BW deck marks the end of Umbreon as a main attacker