Alexander Gregory, from the early days of the game
She grants hexproof to your permanents, which limits targeted interaction and preserves key threats, and she lets you cast Angels from the top of your library to keep pressure consistent without overextending your hand
You're going to want a mix of cheap equipment to put into play early and discount your commander, and expensive haymakers like Kaldra Compleat and Dragon Throne of Tarkir to free-cast off of Nahiri's attack trigger
On top of that, it synergizes exceptionally well with Ninja of the Deep Hours, as it packs evasion, and since you can return it to your hand, you can keep scrying multiple times throughout the game
If a card with no mana cost gains flashback, it has no flashback cost
Honorable Mention: Incubator Tokens The Incubator tokens from March of the Machine featured on some of the strongest cards from 2023 (Chrome Host Seedshark, Sunfall), to the point where they almost overshadowed the big splashy battle mechanic from the same set
