While keeping your multicolored card count relatively high will make your Niv-Mizzet draw more cards on average, it may very well make the rest of your deck weaker
The God-Eternals are four gods that appeared in War of the Spark : God-Eternal Kefnet, God-Eternal Rhonas, God-Eternal Bontu, and God-Eternal Oketra
Heres a general list right now of value: 1 Booster Pack: 1 fairly playable rare, 1 bad Prime (or Legend piece), or one strong staple Trainer
There are very few cards that do that
Orphan, Cocoon falCie Muldrotha, the Gravetide is still a huge beating in Limited
You can punish players by stacking ETB damage abilities like Warstorm Surge or Pandemonium, or you can get creative with Confusion in the Ranks and continuously exchange Norin for some of your opponents permanents