Nahiri's Machinations
Oracle Text
At the beginning of combat on your turn, target creature you control gains indestructible until end of turn.
: Nahiri's Machinations deals 1 damage to target blocking creature.
Card Rulings
4/8/2016 Players can respond to the triggered ability of Nahiri’s Machinations by destroying the creature you target before the ability that gives it indestructible has resolved.
4/8/2016 Destroying a blocking creature doesn’t cause the creature it was blocking to become unblocked.
There are about 12 vampires revealed in SOI so far and only Olivia's Bloodsworn can't block.