It also has the same name, so if you copy a legendary creature you control, you will need to choose one of them to put in your graveyard due to the legend rule
As I write this, Vivi is becoming a problem for Standard
If you want to cast a lot of spells and attack, Adeliz, the Cinder Wind is the Spellslinger for you
Its a bubble, and it will burst, but the concern is just how much harm it will have done by that point
However he will not be the best deck because the new Lucci4 crushes him, HARD
Mox Amber Yeah, its a Mox, but Mox Amber is part of the balanced Moxes that were deliberately made trickier to use so as to not make them auto-includes