More than 90% of split cards have a multicolor color identity
In a game where you can already get three prize cards from knocking out a Mega Pokemon, having a card like Iron Hands ex around that adds an additional prize to that could be something of a problem, so its probably for the best that card rotates out
But where Exhume can lead to some nasty blowouts or fall off quickly after the first few turns, Stitch Together offers the most natural condition most graveyard decks could hope for: you just have to load up your yard a little, and away you go
The Shadow Lord Gix, Yawgmoth Praetor was a pretty strong mythic in The Brothers War, and it should play out fairly similar here
In 1994, when Wizards of the Coast decided to create sanctioned tournament play, the Power 9 were restricted in the very first Banned & Restricted announcement
[2] You can target 1 face-up card your opponent controls and 1 Level 8 or higher DARK Pyro monster in your GY