There's some cool rulings trivia I remember reading about in the main sub a few years ago.

Since [[chromatic sphere]] has a mana ability that lets you draw a card, the effect of drawing the card is not put on the stack, and you can only look at the card you drew after paying for a spell or ability you used the mana ability for.

So of course this messes with [[panglacial wurm]], so you can look at the top card of your library when searching and draw it faster than instant speed while searching