Theres just one catch: your opponent has monsters too
Heres the Low & High Card Count worksheet showing sample data: Numbers are only visible in cells with card counts of one or higher
Take, for instance, the below works on Yidris, Maelstrom Wielder by Michiko Kanda Sablan of Sablan MTG Alters, Nin, the Pain Artist by Toriy Abdel of Magic Fantasy, and on Arixmethes, Slumbering Isle by Marisa Capitao of Captain Magic Altered
Branded Opening can Summon a Despia monster from your deck by only discarding one card from your hand
There have even been entire sets with zombies as a central theme, like most Innistrad sets or Amonkhet and Hour of Devastation
If theres too much countermagic, too little ramp, too many big threats and not enough ways to survive long enough to play them maybe your commander needs a critical mass of a card effect you thought you had, but didnt