Exploit means When this creature enters, you may sacrifice a creature. 702.110b: A creature with exploit exploits a creature when the controller of the exploit ability sacrifices a creature as that ability resolves.
He allows you to maintain board presence while simultaneously digging for the specific tools you need to counter your opponents strategy
(2022-02-18) An Equipment creature can never become attached to itself
Typically the kinds of deck that want coverall counterspells also want to leave mana up to be reactive, having to tap five mana in your upkeep will make the turns following a Pact of Negation deeply uncomfortable until you have lots and lots of mana
So let's see which cards with the ability get played the most in commander
Notably, Hildibrands Adventure spell, Gentlemans Rise, triggers the decks Commander Yshtola, Nights Blessed, dealing two damage to all opponents while you gain two life