Find these variants only in Collector Boosters
And by feel blue, I mean lets check out these great blue cards
Illustrated by Magali Villeneuve Standard Not Legal Alchemy Not Legal Pioneer Legal Historic Not Legal Modern Legal Brawl Not Legal Legacy Legal Comp
While you can try to stop the deck, counterspell one of the pieces, or discard them from your opponents hand with the likes of Thoughtseize, this is primarily true for many of the combos listed here
Even if one isn't playing those colors or doesn't have Channel-Fireball, a Black Lotus can give a nice mana bonus for a player, allowing them to play powerful cards in the early game
UB poses a real financial threat to the hobby, but it's simply because of how much people want these IPs in the first place