Feel like these posts should have spoiler warnings. The game I picked is Hollow Knight. * Spoilers Ahead for Hollow Knight* Nightmare King Grimm. One of the first bosses to really annoy me in this game. Spent ages figuring this guy out. To beat him, you need to learn his patterns. Also, he's quite random in the attacks he chooses; therefore, you need to learn to read his telegraphs. Tough, but doable.