Both paths through Tomb of Annihilation feature room effects which should cause a Sefris trigger from discarding or sacrificing creatures (including tokens), but if Sefris was already the reason we were venturing in the first place her once per turn stipulation means we cant take advantage
Brago only gets stronger as power creep pushes cards further, with options like Agent of Treachery, Dour Port-Mage, and Elesh Norn, Mother of Machines that stand out as a few examples of recent upgrades to Brago
(The same is true for card types that don't appear in most games, like plane or scheme.) You can't choose a subtype, such as creature types like Spider or Hero, artifact types like Treasure or Food, or enchantment types like Aura
Theyre just placeholders, although they can sometimes look so authentic that someone else could pass them off as real