It has affinity for artifacts dorks only
Karn, Legacy Reforged The MTG artifact creature that artifact creatures love best, Karn, Legacy Reforged is great whether you're going wide with lots of little artifacts and tokens or tall with a few massive ones
The only possible explanation I can see for this is that Changeling OutcastChangeling Outcast is more well known than its artifact cousin, as other than the fact that it can be DisenchantDisenchanted, it's strictly better
That high Willpower gives him a certain freedom to Quest too, as he can soak up a decent amount of damage when Challenged
Choose whether to cast the third spell without paying its mana cost
When it attacks, it exiles the creatures that crewed it, then brings them back at the end of the turn