This may not sound too strong, but time and time again, one simple mana can be all you need to win a game or comeback from a rough situation, and nearly every Commander deck needs a Command Tower
Ursula combos with any Song that costs three or less (ok maybe not ANY, sorry Reflection), but Bibbidi Bobbidi Boo and Mother Knows Best are both within Emerald, her starting color, so I expect them to see the most play overall
Typhoid Rats is a perfectly decent blocker for your early turns
Get ready for a deep dig
Then, the next player makes their choice, that effect happens, and so on for each player faced with a villainous choice. You may be thinking: Wait, that's not how it works
Fetching a Basic, a Stage 1, and a Stage 2 Pokmon all at once massively accelerates setup