if you have items on the ground and then die, some of those items can fall thru the ground into the void when you come back to the area
steps to reproduce
kill the mosstrocity several times and do not pickup any items (reset to checkpoint after killing it)
respawn the boss again and then die
teleport back to the area using the totem at brave haven, or reset to checkpoint.
you will see multiple items fall thru the map
this happens with any area or boss, but its more likely with the far away zones that get unloaded when the player dies.
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