Keystone mastery that doesn't require an enemy champion.

So, there is a lot of talk about people wanting masteries removed, especially keystones, because they make or break certain champions. That's a long discussion that I don't want to open up here, but seeing all the keystone masteries that exist right now, I've realized that there isn't a single one, apart from Bond of Stone and Windspeaker's Blessing that works against monsters, and even those have a very small part that actually does. I think that Warlord's Bloodlust also benefits from minions, but that's about it.

I really think that there should be some sort of keystone mastery that interacts with minions / monsters. Kind of like the old CoC, that granted max HP whenever you killed a monster or cannon minion. Now, I don't want one that becomes a MUST HAVE for like every jungler in the game, but I believe that there can be at least one mastery that can work well on let's say junglers, but is not a must have. Even when the +300 HP one was out, I still played Elise with TLD, because I liked the extra damage and snowball potential it offered, so it wasn't as straightforward.

What about, let's say, a mastery that grants damage reduction or amplification for a short period of time after you kill a minion or monster? Or maybe increased movement speed? Or, after killing a minion or monster, your next AA deals increased damage (kind of like the old Serrated Dirk)?

I believe there are some ideas out there, but generally, I believe there should be at least one keystone mastery that doesn't require an enemy champion to work.