Market research showed that hybrid mana was the highest-rated thing in the original Ravnica block, and I believe it is still one of the highest-rated "mechanics" (it's a tool, not a mechanic, but that's what the market research called it), if not the highest, of all time
While Urabrask is undoubtedly an extremely powerful threat, it is important to note that it doesn't bring anything to the board in those cases where it does get immediately removed
Though many Pokmon TCG fans merely collect cards, there is still a good chunk that plays the tabletop game itself even if not on a competitive scale
[+1]: Target player mills two cards
This will be right at home in decks with high mana value cards and will likely play quite nice in slower decks without all the zero to one drop ramp/rituals or low cost interaction
Its also a Faerie, meaning that if your deck likes Nightveil Sprite, it might well want a second copy