The downside of granting your opponents an additional land is one you shouldn't take lightly and if playing against Izzet or Simic decks, but this card gives you the chace to get cards like Ouroboroid, Badgermole Cub, and Slickshot Show-Off out of play before they have the chance to do any real damage
If an opponent has already assigned energies to their card, they will defeat Snorlax quickly , and in that case, there is no point in using Tanks
Whether its using Leyline Bindings Domain reduction or Impending the Duskmourn Overlords, you can cast enchantments with massive mana values for cheap and transform them into gigantic creatures with Enigmatic Incarnation
Many mana dorks exist, and quite a few are better than this one, but none are legal in Standard
To cap off Eidos support package is his ability to be special summoned from the graveyard
Mono white makes it a little harder but there's still plenty of blink to get some serious value here, and then you can deal with problematic permanents