I mean yeah I guess there's the restriction you can't copy an opponent's creature but I don't think that's particularly relevant when we're talking about cards you use for combo purposes
While almost all the vanishing cards get better in combination with Solemnity (not you, Tidewalker), some really shine
If youve got Experimental Frenzy out and cant cast cards from your hand, or you have none in your hand because youre red, Chaos Wand makes sure you always have something to do
Added bonus of thinning out your deck
The Brothers Hildebrant cards were utterly gorgeous, for instance, and are deservedly expensive
Tragically, a better four-drop in red and green came along side Ashroot Animist, Halana and Alena, Partners and it just does so much more