Several times now I have experienced at some point midway through games of crucible matches, invisible players of every type, consistent with the visual bands of color specific to the light-burn of a weapon failing to load its model... Or perhaps a Guardian spawning in. Upon shooting them my model also disappears, both weapon and body. The only correlation I believe it could be is the completion of one of the new Tribute bounties. These also fail to display a completion until you have opened the pursuits tab, unlike every other bounty type in game.