They're a great way to expand your collection and potentially find some hidden gems
I recommend: Sol Ring, Mana Crypt, Mana Vault, Grim Monolith, Ruby Medallion, and that new card Jeweled Lotus
Are they the same entity with two bodies
But as popular as these targeted discard spells have been through the years, they are usually just one tool in a balanced list
The Wording Updates "Add" Lands have had wording that refers to "your mana pool" since the game's inception, but the mana pool is not a big part of playing the game (most people just tap lands to pay for things without ever using an intermediate holding place), and the term is a constant source of confusion for players learning the game
As long as you set up your discard pile, you can recycle two Energy and immediately attach it to two of your Ancient Pokemon