For casual play, skip expensive duals like Underground Sea , they matter only at the highest competitive tiers
Traditionally incapable of attacking, walls are by far the most defensive creature type in Magic: the Gathering
Alternatively, as a finisher, I could use Unpredictable Cyclone which can easily get me an exile until for the entire deck if I only play one of that card type in the deck
Maybe you want their planeswalker or artifact instead
For example, you have a .071% chance (7 in 9993 odds) chance of pulling a shiny, non-full art Weedle whereas there is a .083% chance of pulling a full art card shiny Beedril ex in Shining Revelry
This ensures your price estimates are grounded in reality, not wishful thinking