The Carnival costs one, shoots one target for one, and then their controller as well
It'll either give you more creatures, burn all your opponents, draw you cards, or put +1/+1 counters on all of your artifact creatures (which most of the creatures in the deck are)
From building your battlefield to planning your path to win , every moment feels meaningful
Be wary of life gain status before casting Withering Curse
Plus, Karador and other leaders that are hard to stop outside of graveyard silencing (The cheaper to play cost, the ability to recur one creature per turn for free) also forces graveyard-centric decks that are just nice and not abusive to have serious issues
Razia, Boros Archangel Karametra, God of Harvests In Karametra, youre going to get lands