So after looking at both Porygon-Z cards from this set, both are fairly even, they both have the same HP and retreat cost, and very similar moves, I like the first move on this Porygon-Z card better, but I like the main attacking move on yesterday's card better than today's, so you really can't go wrong with trying to incorporate either card into a deck
When Commander 2019 came out I made techs for eight different commanders half of which I did two for and with Throne of Eldraine I'm currently in the process of working my way through the Brawl-centric commanders
Those games can be tough but outside of that, this combo is extremely deathly and often results in runaway games
The art gets moodier (no more happy-go-lucky vibes here)
Whats The Meta
And the Mardu versions of the deck are also adding Chthonian Nightmare, which is basically just a fixed, energy-based Recurring Nightmare