So #Loki found the one guy who wasn't tossing pointy things at Baldur as a "joke"--not because Höðr thought that it was a poor joke to throw projectiles at his brother (even though it was) but because he was blind and couldn't enjoy the joke as much. Well, Loki gave him what he wanted, in the form of a mistletoe spear and a helpful guiding hand, and Baldur went down. (One suspects that Höðr was secretly pleased; his prettier brother probably got the lion's share of his mother's love, and one doubts that Frigg would have made _anything_ promise not to hurt Höðr.)