You can only use each effect of "Phantasmal Summoning Beast" once per turn
Shadow Rider Calyrex is a bit of a "midrange" deck in the sense that it can do many different things during the game: it can KO opponents Pokmon with one big attack, it can negate prizes with healing, and it can slow down the game with different locks (Frillish and Wobbuffet) Why it wins Well, to put it simply, Calyrex can do many different things and all of them are very strong
SR Super Rare Puppet Plant X EARTH Level 3 [ PlantEffect ] ATK 1000 DEF 1000 You can discard this card to the GY, then target 1 Warrior or Spellcaster monster your opponent controls
Jigglypuff's Sing attack is particularly powerful and may make a splash, providing sleep support for a variety of decks
While 1/1s will take some time to whittle down life totals, cards like Favorable Winds and Sprite Noble can add significant power to your board for very little mana, turning a bunch of unassuming creatures into a dominant board