If you're losing on turn 5 because you didn't wrath on 4, you probably don't even want wraths in the deck, you want counterspells and spot removal
Any "as [this artifact] enters the battlefield" or "[this artifact] enters the battlefield with" abilities of the artifact will also work
What counts as art when judging an Un- card
It does go up in value in decks that have lifegain synergies (Vito, Thorn of the Dusk Rose or Karlov of the Ghost Council, for example)
Some of the more popular cards players are already seeking out include Badgermole Cub, Firebending Student, Tenacious Tactician, Redirect Lighting, The Cabbage Merchant, Wan Shi Tong, Librarian, The Walls of Ba Sing Se, and Momo, Playful Pet