Pernicious Spore Bomb (Greater)

This flask contains fast-growing mold spores, which quickly take root but just as quickly rot away. You gain a +2 item bonus to attack rolls. The bomb deals 3 poison damage, 3d4 persistent piercing damage, and 3 poison splash damage. Except on a critical failure, the bomb's splash area is coated in vegetation, becoming difficult terrain for 1 round.