They get better in multiples too
Trainer cards can further be classified into different types: Items: these are the primary usefulness of a deck, with generally limited power levels
Also, because of how this card works, it's not necessarily correct to put Macro Cosmos in a Ghoti deck (though it is strong if you do, of course)
I also like Hua Tuo, Honored Physician to take a dead creature and put it on top of your library for Durnan
Sometimes a friend, more often an enemy, billionaire Duelist extraordinaire Seto Kaiba, pushed the Pharaoh to his limits from the very first episode
This is doubly important because, while we can rely on McDuck Manor in theory for a win condition, we cant afford traditional board wipes such as Be Prepared or Sisu Empowered Sibling