For only three mana, you can tap [c]Arena[/c] to have a creature you control fight a creature an opponent controls of their choice
What affects the value of Porygon2
Packs may contain Special Guests, Mana Foils, Extended-Art cards, plus borderless cards, Rares, and Mythics well-positioned to become your collections new crown jewels
(This includes disguise, cloak, and in games involving older cards, morph and manifest, as well as a few other effects that turn cards face down.) Common methods for doing this include using markers or dice, or simply placing them in order on the battlefield.
Perhaps it's the relative weakness of the card keeping the price down or the traditional take on this character
It draws a given number, in this case four for five mana, one more mana and card than Harmonize, Concentrate or Ambition's Cost