For where Pikachu fits among all the grails, see our most valuable Pokmon cards guide
First, we've got Trial // Error, a split card that combined has Esper colors, that is, until you realize it doesn't have the fuse keyword that would let you cast both parts of it
Can players respond after they see what's going to happen
As I mentioned above, Treasures are rampant in Commander
It can be used not only in a defensive way, clearing annoying ETBs or powerful abilities, but also in an offensive way, making Deaths Shadow 13/13 or Kroxa, Titan of Deaths Hunger a two mana 6/6
WU: Artifacts Matter The easy thing about drafting these colors is that its very clear which cards support your strategy (the ones that say artifact in the typeline or rules text), and there are lots of them