As for a2-7-yanmega-ex, Air Slash deals 120 damage but will discard an Energy, so you're forced to attach another Energy if you want to attack with it again
As more and more people collecting cards in the poopoo QC era (some ex, DP, BW, XY) get priced out of the PSA 10 versions, CGC 10/Pristine is the only logical way to go about set building
Even removing Nether Void is going to cost someone an additional three mana, so you're getting some value here no matter what
So, we usually ask the artist who can draw that Pokemon with the most charm as a basis
Card Type / HP / Stage:Lightning / 60 / Basic
While at Magic30 last month I spoke to Principal Art Director Taylor Ingvarsson, who was the lead AD on this set, and has used Mayer as an artist on every major set hes directed