Arachnoform

In Commander, Arachnoform is a niche tribal enabler that earns its slot almost exclusively in Spider-synergy decks or alongside commanders like Treebeard, Gracious Host who care about the type being present. At one mana it's nearly free to slot in, but it does nothing in isolation — you need a payoff already on the battlefield or in the command zone to justify the inclusion. Pauper is where the card has the most theoretical reach outside Commander, since cheap enchantments that grant evasion-adjacent keywords to every creature can matter in go-wide green shells, though Spider tribal isn't a competitive archetype there. In Modern, Pioneer, Legacy, and Vintage, Arachnoform is too narrow and too low-impact to see play — formats that reward individual card power have no use for a blanket type-setter with no attached stat boost.