Arena is great in that is a free experience for everything, but it can also have some major downsides
This approach suits Commander best, where singleton formats reduce consistency concerns and longer games give you time to fix mana
That makes it a solid choice for green decks that want consistent fixing or value over time, especially in enchantress or bounce-focused Commander builds
Krark-Clan Ironworks, Tezzeret, Master of the Bridge, and Urza, Lord High Artificer will also help us cast more spells, either by sacrificing something or tapping artifacts to pay for them
Honestly, I feel it belongs in the Forbidden section, but for now it remains at 1
Some great options to summon here are Invoked Cocytus who can attack while in defense position, or Invoked Mechaba who can negate spells, traps, and monster effects