Each Dragons on this list is chosen for its power, popularity, impact in competitive formats, and enduring appeal
Also, unlike the other lands in the cycle (and most other creature lands in general), Den of the Bugbear can actually add something permanent to the board, since it creates a Goblin creature token
Added Shoot First
Because today is the final day that the Prime Big Deal Day concludes, these prices will not last.
You could easily draw one or two extra cards each round with this in play in a four- or five-player match
It doesn't copy whether that creature is tapped or untapped, whether it has any counters on it or any Auras and Equipment attached to it, or any non-copy effects that have changed its power, toughness, types, color, or so on