Acolyte of Bahamut gives Karlach the ability to discount the first Dragon spell by two mana, and Dragonlord's Servant and Dragonspeaker Shaman give mana discounts to Dragons
For those pesky tokens decks, Cinder Giant is here to keep their board clean from saprolings, vampires, soldiers, or whatever flavor of expendable creature your opponents run
As a result, Destined Rivals has explosive hype behind it to rival Prismatic Evolutions and boasts several chase cards
Power Frame is not a complicated effect by any means, but the way that the card is worded looks like one of those memes of how Yu-Gi-Oh
After the Kanto starters, though, value starts to dwindle
This works out quite well, as Elminster's +2 allows you top draw a card and scry two, reliably allowing access to this cost reduction