some people believe that Master Sets must include Promo Cards, Alternate Releases, Variations, and Error Cards to be considered a true "Master Set." Others argue that there are cards far too rare or expensive to be considered part of the set they were released with - for example, the "Pikachu Illustrator" card would be difficult to include as part of any Complete Set or Master Set
MOM has a bonus sheet, Multiversal Legends (MUL), consisting of reprints of legendary creatures, some of which (like Atraxa, Praetors' Voice or Ragavan, Nimble Pilferer) are long-time MTG staples
The latter costs twice as much for a 2/4 but with flying, giving her much more range and size
6 Morophon, The Boundless If you want to play with all five colors in your Dinosaur Tribal deck, then Morophon, The Boundless is the commander for you