Near-Death Experience Lands ravaged, cities in ruins, so many lives sacrificed, and yet there was no other word for it but victory
(If this creature has no +1/+1 counters on it, put two +1/+1 counters on it.) Permanents you control have Whenever one or more +1/+1 counters are put on this permanent, put an additional +1/+1 counter on it
While that's not the most terrible idea, the likelihood in a Niv-Mizzet deck is that the other spell you're casting is a burn spell that could do the same, and I have to feel that you're going to be better off casting it by itself, rather than putting all your eggs in one basket
It enjoyed a premium position in cube when I still had the cycling lands in and continued to enjoy a locked in slot in a number of constructed theme decks such as Seismic Swans or Lightning Rift decks
Probably better suited as a 99, though not an awful choice to head a discard-themed deck