Most bizarre bug ever:
— the shields used by some of my characters (only a few of them) mysteriously did not show up in battle
— I assumed that the shields had been smashed by an orc and that I’d forgotten to equip them with new ones, but the shields were still shown in the character inventories and were still shown in the characters’ possession in the turn-order panel towards the bottom-right of the screen, and the shield-specific skills were still available to select when it came to those characters’ turns (see, in the first screenshot attached, that Ludolf, with a fighting axe and full helm, has a rare red triangular looted shield shown in the turn-order panel and is able to use shield-specific skills with it, but that the shield is not visible on the battlefield)
— towards the close of the battles in which this happened, the invisible shields suddenly started falling from the sky, back into the possession of their owner, as if the gods who were pleased with us had overslept and missed most of the battle (see second screenshot attached)!
There was nothing obvious causing the issue to occur. However, I’d been fighting lots of orcs (and having shields smashed) and killing lots of bandit leaders (and looting rare and special shields), and I had switched around shield ownership quite a bit so that each character had shields suitable for more than context. Not all of the disappearing shields were rare/named ones, but I think all of them were ones that had switched ownership.