That's quite the combination of cards, even if you're talking about 9 mana and then some for the whole package without affecting the board in the meantime
However, if you don't use the effect on the first spell you won't be able to use it on any spell that turn
The issue is more that I'm not 100% sure where to put this, as I feel like it's ideal in a situation where you have creatures with big ETB triggers (or death triggers if you're trying to sacrifice the tokens so you can make new ones next turn), since this is pretty much asking to eat removal after you connect with a player
It may be exciting if you draw a rare card like Sephiroth, Fabled SOLDIER, but if it's your only good card that uses black mana, you may not want to build a deck around it
Ive tried many strategies at trying to break serve against Gideon, Ally of Zendikar + Wingmate Roc, but the best Ive found so far is to be as aggressive as possible to try to beat them at their own game