Ursula, Deceiver of All Finally revealed as the big bad villain of Lorcanas running story - and also given the Enchanted Rare treatment in this set as revealed here on Dicebreaker - Urusula, Deceiver of All gives a new incentive for song-focused players to peel away from the dominant amber-steel focus to try giving emerald a spin instead
This effectively makes its ability to pay one black, draw two cards, and potentially remove a problematic creature from the board
With all these benefits, why wouldn't one want to run nothing but Special Energy
Descended is a keyword action on cards that asks: Have you put permanent cards into your graveyard this turn? Some cards, like Molten Collapse, just care about you having descended this turn, no matter how many times
The colors used were a bit plain, and some types (like Dragon and Poison) had two colors but they worked