Sure, it can hit the opponent reasonably hard for the cost, but it also dies to everything, including lots of cheap removal and creature ETB abilities
Their arms have either worn away or been deliberately removed and they now paint with two brushes that are attached to them, using blood from their own veins
In a deck focused around challenging characters, removing the option for your opponents to keep their characters ready is quite powerful
Having too many of these moments also risked distracting from the larger focus of depicting action, worldbuilding, and whimsy
Easy pick for our Halfling Food Tribal
This card will shine most prominently in non-singleton formats like Explorer, allowing the player to run multiple copies of Fog in their deck, recurring the effect as many times as they can cast copies of the card