Everybodys got their tuned decks led by Korvold, Alela, Prosper, Atraxa, what-have-you, and Im the guy that shows up with Boris Devilboon and wont shut up about how Jesper Myrfors refused to draw me a minor demon token in 2013
I personally play them in place of actual lands, but then, Im also a big believer in playing them as lands
Together, these abilities give OP11-041-nami decks strong resilience and a straightforward but highly effective gameplan in the current meta
It has a low casting cost, and since many infect creatures are cheap to cast, it's likely you were able to get a few infect counters on your opponents, allowing for Yawgmoth to begin using its proliferate ability to add on more to them
Japanese cards are often praised for tighter quality control, which can reduce variance