Unlike Jitte this effectively charges throughout the game with no need of it in play and so you can flop it early and deny people strategy options or you can bait them in and flop it down once it is too late for them
Effectively, you have to pay 6 Mana just to give a Creature a +3/+3 boost
Whenever you remove 1 or more damage from a character, you can ready Aurora
They only cost anywhere between one and three mana, and they'll stay on the battlefield until destroyed, bounced, or sacrificed
The ability to investigate every time a land enters the battlefield is just absurd value, especially in formats with Fetch Lands
The threshold for free shipping is high, but they have a decent selection of singles and sealed Magic products