This Horror also has an ETB to mill until you mill X dorks, so that'll fill out your graveyard with dorks and the rest'll head to the bottom of your library
This is why I believe the Monstrosity could work whereas Sliv-Mizzet didnt
Example two: Our cunning opponent attacks us with a Minotaur Aggressor, we block with a Bear enchanted with Bear Umbra
Steel Overseer pairs especially well wit h Unwinding Clock, since you can use its effect four times in a full turn cycle, giving four +1/+1 counters to all your creatures by the time your next turn starts
Finishers/ Surprise /Alternate win conditions Of course Apes have some great big hitters
If Infesting Radroach is milled at the same time an opponent mills a nonland card (for example, because of the activated ability of Raul, Trouble Shooter), Infesting Radroach's ability will trigger