Over the years, Wizards has toyed with many different flavors of Sagas--variable number of chapters, all kinds of effects, creatures that transform into Sagas, Sagas that transform into creatures (especially in Kamigawa: Neon Dynasty) , and even an Enchantment Land that's also a Saga
Yuna, Hope of Spira The Elder Dragon War Overlord of the Boilerbilges The core game plan centers on reanimating Overlord of the Boilerbilges from the graveyard
Its an artifact, with a simple cost, and a simple ability, that is right for its color
Summon: Yojimbo fits well with Tom Bombadil as a commander, buying Tom time to dig through its deck
Having Aragorn as the commander wouldve made more sense, especially since hes the one to convince King Thoden to march towards Gondor