They wanted to highlight Magics iconic creature types while showing off some historically iconic cards but failed in both regards
What pushed him into nearly every worthwhile deck around the time of his release in 2015s Battle for Zendikar was the fact that he could lay down an emblem, which permanently buffed every creature on your side of the field with one extra point of power and toughness
They also have dedicated land support with Haven of the Spirit Dragon, Crucible of the Spirit Dragon, and Temple of the Dragon Queen, making it easy to support a 5-color dragon deck
Set: OP-15 Adventure On Kamis Island
on the surface, it looks pretty underwhelming, but when you dig in, its actually a very solid value proposition
This is easily done within the confines of the precon, both with the commander that investigates every turn to make a Clue and with various draw spells to trigger all of your permanents