When cast on any layer of Acheron, the bladestorm spell summons 1d6 shards of the razor-ice of Ocanthus. Each shard strikes with a THAC0 of 11 and inflicts 1d8 points of damage per level of the caster, plus severing the target's head on a roll of 20. A target creature making a saving throw vs. spell takes only half damage, but there's no general protection against the beheading effect other than a protection from normal missiles spell or a brooch of shielding, both of which deflect shards directed at the protected creature. The shards attack once per round until they hit a target, then shatter, leaving only bits of murky water behind.
Notes: Very rare spell, useful primarily on the plane of Acheron in the Planescape setting.