31 Karn, Silver Golem Animate Your Own Army For those looking to build an artifact deck completely devoid of color, running nearly entirely artifacts, Karn, Silver Golem is a solid choice
The cost would be the combined cost of both halves, they would be put on the stack as a single spell and would resolve starting with the left half (which usually made the right half work better anyways)
Some cards like Turn to Slag, Fires of Mount Doom or Molten Rebuke destroy equipment attached to creatures they kill, but thats an effect of that card
The Casual vs Competitive Problem When considering high-end Commander, whether competitive in nature, or in name (like cEDH), I think this argument is most watertight
(And dont forget key artifact creatures like Stuffy Doll and Snow Fortress as well)