You wont have to worry about your spells getting countered by anything, and any Fog effects wont stop your Spiders from crashing in for damage
However, it can take time to build up a board strong enough to take on some of the stronger decks, making it a rather slow deck
Add in the fact that four mana is a metric ton for what is essentially draw a card with downside, and I really dont see a reason to play Rona, let alone make him your commander
This vampire rogue legend from New Capenna is your classic instant- and sorcery-based spellslinger commander
Great Commander decks arent strictly monotone
Showcasing Sultai colors BGU (Black, Green, and Blue), the Precon features a theme built around counters and Proliferating those counters