Master of Cruelties does this during combat, Vraska, Relic Seeker does it as a planeswalker ultimate, and Worldfire just does it
A bigger magic deck can dilute your best cards, which reduces your chances of drawing them at the right time
No, you can't pick up your seat and go through doors to find more doors to increase the value of X
In Commander, resolving one of these bad boys (or having one put into play via more nefarious means, such as with Muxus) is often enough for you to pull well ahead of your opponents on board
Or without having to pipe up and ask someone
You can find printable binder inserts online specifically for Pokmon cards, or even design your own simple backgrounds to enhance the theme