Some doors have abilities that trigger whenever you unlock that door and require one or more targets
Iconic Cards: Tarmogoyf, Dark Confidant, Lightning Bolt, Birds of Paradise, Liliana of the Veil Popular Decks: Abzan Junk, The Rock, Jund, Superfriends 4 Tempo Tempo decks aim to stay one step ahead of their opponents by ruining the opponents plan
Also dont forget that any amount of deathtouch damage is lethal, so using ping abilities like Viridian Longbow with deathtouch is a wonderful and reusable kind of removal
Affordable, easy, and environmentally friendly
Because this bounces back to hand to do the thing, you cant build an engine around sacrificing one Minister of Inquiries to get back another, netting energy
You need to make the effort to trigger it on turns other than your own, but the payoff is there