Provided you run a deck with a lot of Spellcaster monsters, it could be an interesting tech card to counter the overwhelming strength of an opponents board
That's consistent with the pattern across the entire Mega Evolution era
More importantly, is that you have a lot of haste to flip Legions Landing on an unexpected turn
Fae of Wishes A key part of stuff to do with your almost infinite mana in Omnath, Locus of Creation decks when that was legal in Standard for a microsecond, Fae of Wishes sees the most play these days as a flexible part of Rona, Herald of Invasion combo decks in Pioneer
Well, the little "and each player" that's tacked onto the end there means that Cave-InCave-In can come down the turn you play your Niv-Mizzet, and draw you six cards to get the ball rolling
"Honorable tactics are for honorable foes