Basically, it only has one universal icon, but when used for negotiation, it becomes four universal icons
Nice control, again, just one
Just look at how massive a transition this was by comparing two artifacts printed on either side of the change: I chose to show you two artifacts for a reason: Mirrodin was full of them
A pile of combos happens in those Jan Jansen decks with cards like Liquimetal Coating to turn it into an artifact and then begin ripping with a Goblin Bombardment in play
When it's special summoned, you can draw a card and discard a card
Some, like Prison and Needle, have been reprinted using art and flavor that obscures their connection to the plane