With the ever-expanding nature of the Historic format, Wizards has taken the opportunity presented to add cards to the format that wouldn't be able to be added through the Standard format
Peak Value: $3,000$5,000 USD (est.) (PSA 9) Why It's Valuable: The most iconic creature from Magic's first expansion, Arabian Nights
Blue bounce spells are the second best tempo cards in limited behind pure removal spells, so a reusable enchantment Unsummon dependent upon playing creature to begin with seems like a card that you'd like to have in your deck
Fuse was born out of the excitement we saw with TDFCs where the player had the ability to access both cards of a two-in-one
You can obviously fill your own deck with enchantments or with cantrippy combat tricks to get a bigger advantage
But just when you thought the issue might be decided, we see the continual dominance of the Bolt-backed Twin, as well as the return of Delver (Grixis style) to the scene