Like most Magic: The Gathering cards, the value of Goldberry, River-Daughter depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (The Lord of the Rings: Tales of Middle-earth)
The bronze variant from the first Lizardon Mega Battle sold earlier that year for $300,000, putting two Pikachus into the upper echelon of valuable Pokmon cards
Theres also Dimension Fusion from Invasion of Chaos, another great swarm tactic that relies upon removing monsters in your graveyard from play
For example, if you target the only Zombie you control with Compelling Deterrence, you won't discard a card
Even better when it's not just sporting an iconic card like Blue Eyes, but is also fueled by nostalgia, arguably one of the major fuel factors of the format itself