The life buffer and damage abilities are nice add-ons, and the icing on top is the card that Omnath draws as soon as it enters the battlefield
The "Build & Battle Box" you'll get at these events include holo promos of either Meganium, Inteleon, Alakazam, or Lunatone -- all with new artwork that hasn't released in Japan yet
On some Thick 1st edition cards you may find a mirrored imprint of a 1st edition symbol right of the Pokball (imprints from Pokmon 1st edition stamps), in the bottom-right corner (imprints from Trainer 1st edition stamps), or in the top-left corner (imprints from Energy 1st edition stamps)
If Entish Restoration is countered, you won't sacrifice any lands
Trust your loupe, not your luck
Plus, the whole point of the Custom Card Contest in the first place is to have fun while making cards