You can also pour infinite mana through Memnarch to take everything your opponents own
Don't do it
Any keywords one of your creatures has is shared across your entire board when you go to combat, so anything with lots of words on it like Zetalpa, Primal Dawn
That means that you can very quickly end up with significantly more land than is fair, allowing you to easily make some powerful moves early on (like, say, playing an eight-mana planeswalker on turn four)
Because it makes treasure, you can really count this creature as fixing, and thats typically a valuable thing to have in Limited, plus this set has some nice treasure payoffs
Infinite Obliteration would be nice here, but Cranial Extraction effects have always underperformed for me, unless theyre specifically there to be cast and immediately win the game