If you gain an amount of life "for each" of something or "equal to the number" of something, that life is gained as one event and Aerith Gainsborough's second ability triggers only once
With that in mind, we recommend a site like TCGPlayer
For better or worse, the other two Bonus Cards dont have this value-based issue
We recommend picking up a few extra packs or trading at local weekly events to upgrade the decks: see our guides below
This estimate is based on the card being PSA or BGS graded
The booster display comes with 24 packs, with each booster packs setting you up with 12 cards, including six Common cards, three Uncommon cards, two cards of either Rare, Super Rare, or Legendary rarity, and one random foil card