(I will note that I treat Thought Scour more like an enabler for Gurmag Angler than a cantrip.) Ive tried Sprite Dragon, Kroxa, Titan of Deaths Hunger, Dreadhorde Arcanist, and Young Pyromancer to try and bolster the roster of threats, and each has its own issues
Run a copy or two in any Izzet deck you build
At the cost of only one mana, Thoughtseize gives you the ability to get rid of a problematic card in your opponents hand, while also granting you valuable information about how to approach the subsequent turns
Unless you have a lifegain theme in your cube this isn't playable anyway but it is a good option and a great piece of redundancy to have for a lifegain singleton constructed build
Whether youre a Spider-Man fan who wants to swing into Commander with your favorite character, or a seasoned player looking for fresh builds, this set has something worth experimenting with