NPC Spawn Issue: Seafuries falling through world frequently

[Lazortag]

When I kite seafuries on my bard, they fall through the world fairly often. I'd say maybe 1 out of every 10 pulls at least one cyclops falls under the world (with just its head poking out). The worst part is when they die in that state, because I can't loot their corpse then. Otherwise they can be unstuck by just running over the water and running back. I'm not exactly sure why these mobs fall under the world more often than others but I figured you should know it's happening.