Budget decks are some of the most popular to build as they dont break the bank
Commander has nearly endless options, but these are my top picks for going infinite
If you want to build a Marrow-Gnawer deck, grab every Rat card you can get your hands on and throw them in
Theres also a space for legends and +1/+1 counters this might be a good Golgari commander for, including cards like Reyhan, Last of the Abzan, Grakmaw, Skyclave Ravager, Polukranos, Unchained, Rishkar, Peema Renegade, Kodama of the West Tree, Renata, Called to the Hunt, and plenty of others
Some battles have devastating back-faces: a literal God, the time-traveling hero Teferi or, a vampire grandma (an all-star in my games)