It only works with permanents, so youre incentivized to play as few instants and sorceries as possible
Secondarily, the archetype's "Unchained Soul" sub-theme focuses on using the opponent's monsters as Link Materials to Link Summon
If you control creatures named Mine Worker and Tower Worker, put two +1/+1 counters on Power Plant Worker instead
The rarer a card, the more valuable it tends to be - however, this is only one factor
It is either obviously illegal for tournament play or has been tampered with in ways that destroy its worth almost completely (inked border, random scribblings on the card etc.) A Poor card will likely have bends, folds or creases in or across the card
Rafiq of the Many and The Ur-Dragon combo off to insta-kill an opponent