Some day well have a more definitive answer here (or if I had a month to go set by set and calculate with the unique number of foils and that particular set of languages), but until then, I think we should estimate higher
In the base set, Mega Garevoir ex, Mega Lucario ex, and Mega Venusaur ex are ruling the top chase cards, with the Illustration Rare / Secret Art Rare artset of the Bulbasaur evolution line a star of the show
An average Pokmon booster box would contain only one rainbow rare card, meaning you were only likely to pull one rainbow from 36 packs
The word Maelstrom should make you take notice
Related #2: Bristly Bill, Spine Sower (Extended Art) Price: $37.40 A cactus Commander that plays into green manas affinity for +1/+1 counters, Bristly Bill is one of Thunder Junctions most sought-after new Creatures for a reason
Part of it, probably, is just what happens when Bolas returns