Start from the 100-card total, subtract your single commander, then fill the 99 using the ratio above: lands first (36-38), then the ramp, draw, and removal cores (roughly 10/9/9), then 7-10 win conditions, and the rest as synergy and flex slots
Playing Yen Sid allows a card draw if a Magic Broom is in play, and having two or more Brooms in play will give Yen Sid a +2 to lore generation
Pull rates seem about standard for 2023-24, a disappointing one in five for a standard ex or better, and far lower if you want to see any of the astonishing number of gorgeous artworks in the set
If an effect allows you to cast Sundering Stroke without paying its mana cost, you can't choose to cast it and pay its cost unless another rule or effect allows you to cast it for a cost
It takes a turn to set up (With the flavor implying its being loaded) and does only one damage when fired, which destroys it
This means if two players both select the Mewtwo booster, they will find themselves earning the same five cards