In the case of Elsa, Spirit of Winter, it helps that the card itself is also one of The First Chapters stronger picks, offering the power to freeze your opponents characters to stop them challenging your cards or questing for lore
Can a Creature With Goad Be Blocked
Also remember that some powerful cards were printed as rares because the mythic rarity didnt exist at the time, like Ancestral Recall, Timetwister, and Time Walk
Magic players love few things better than drawing an extra card, especially when it doesnt cost them a resource, so I expect youll find yourself safe from attacks from at least one opponent each turn
But if you like big, splashy Dragon tribal plays and winning through overwhelming threats, Tiamat does the job cleanly