If you exile your entire library without exiling a legendary nonland card with lesser mana value, you will randomize the exiled cards and they again become your library, ending the effect
Aegar, the Freezing Flame Axelrod Gunnarson Bartel Runeaxe Beluna Grandsquall Bonny Pall, Clearcutter Bre of Clan Stoutarm Brion Stoutarm Dargo, the Shipwrecker Gorm the Great Jareth, Leonine Titan Kalemne, Disciple of Iroas Kroxa and Kunoros Kroxa, Titan of Death's Hunger Oloro, Ageless Ascetic Osgir, the Reconstructor Phlage, Titan of Fire's Fury Rosheen Meanderer Rosheen, Roaring Prophet Ruhan of the Fomori Storvald, Frost Giant Jarl Surtr, Fiery Jtun The Lady of the Mountain Thryx, the Sudden Storm Uro, Titan of Nature's Wrath Vogar, Necropolis Tyrant Yorvo, Lord of Garenbrig Zalto, Fire Giant Duke
Compare this to...removal like Vindicate that is pretty common at the kitchen table and in Commander
We just want our creatures to be undeniably unblockable, and so lets dive into the unblockable-enabling cards
Unfortunately the card does miss on non-Legendary Creatures though, which contributes to why it isnt higher on the list