Champion of Wits is the real deal, and if this list were simply based on the amount of play cards will see at the beginning of the format, then it would be even higher up
I mean, sure, you can also exile your stuff, if you want, but its pruning our opponents yards thats the goal here
The combination of excellent colors for the Commander format, a body with so many good abilities, and the free proliferate effect is tough to beat
Insects are often moving in and out of the graveyard, making Amzu the perfect support card for it
Your odds are slightly better here: 1/64 for a specific rare and 1/128 for the specific mythic EA/Showcase/Borderless
Theres a little competition from cards like Glare of Heresy and Revoke Existence that often do similar jobs, but I think well find that being an Instant is a lot more valuable than killing the few nonenchantment artifacts that see play and that there are enough nonwhite enchantments that you cant rely on Glare of Heresy to answer enchantments (though Glare of Heresy will keep seeing play, just not in a competing role with Deicide)