Merciless Javelineer
Amonkhet — uncommon
Creature — Minotaur Warrior
Merciless Javelineer rulings:
2017-04-18: Once a creature has blocked, Merciless Javelineer’s ability can’t undo that block.
2017-04-18: The target creature won’t be able to block even if the -1/-1 counter is removed from it or if the -1/-1 counter can’t be put on it.