While raw or played copies can be found for reasonable prices, high-grade 1st Edition copies in perfect condition are an entirely different financial beast
Its relatively easy to counterfeit Magic cards
Even with just a single Drowned Secrets on the battlefield, something like Merfolk Secretkeeper (both the adventure and creature modes) into Callous Dismissal on Merfolk Secretkeeper into Merfolk Secretkeeper again ends up milling 18 cards for a total of six mana, making it a great way to close out the game once our opponent's library starts to dwindle
It becomes prepared if an opponent controls more creatures than you (after it creates an Inkling token), and its hit just shy of $18 at the time of writing
Wildfire + Burning of Xinye Wildfire and Burning of Xinye are cards you can build a deck around, especially in formats like Cube
Plus, its one-time ETB effect will be hard to exploit, especially since we have to pay the 5 mana each time we want to tap down the board