Explore is a tremendously flexible mechanic, and it becomes even more dynamic when you trigger it in bulk like this
Added Survival Instincts
5 Bruvac, the Grandiloquent Goes All-In With Mill 3,664 Decks on EDHrec.com For many years, MTG players considered "mill" to be an almost-good effect that never became competitive
If their deck utilizes the graveyard, then Faithless Looting is even better and has no downside at all
Balan, Wandering Knight can single-handedly push your opponents into despair if equipped with Lightning Greaves and Behemoth Sledge early, which both have low mana costs
We've seen cards like True-Name Nemesis and Containment Priest from past Commander sets maintain significant value, but at first glance, it doesn't seem like there are any Legacy standouts hiding in Commander 2016 , so this exception probably won't be relevant to our discussion