Divide by Zero is a Instant that returns a spell or permanent with mana value one or greater to its owner's hand then you can Learn
Whenever Grimgrin attacks, destroy target creature defending player controls, then put a +1/+1 counter on Grimgrin
For instance, Patchwork Beastie will be able to attack, Impossible Inferno will exile cards off the top of your library, and Scuttletide will give Crabs you control +1/+1
You can see it in every game piece in the set, but the art design team took it a significant step further with the release of scene cards
Indeed, only a few competitive staples are included here, meaning you will have to combine it with staples you already have to make it more competitively viable (more on that in my upgrade guide)
I believe the quantity of Revolutionist you want in your deck depends on the number of removals you have