Things that Increase Critical Threat Range
Disciple of Dispater 4, 8 (Book of Vile Darkness) 3.0 MaterialWhen wielding an iron or steel weapon, the natural threat range of the Disciple of Dispater’s weapon doubles, then at level 8 it triples instead. This ability stacks with the Improved Critical* feat, but not the Keen property. Requires Evil alignment to take.
“Streetfighter” Barbarian 7 (Cityscape Web Enhancement) When a Streetfighter Barbarian makes a charge attack or attacks a flat-footed opponent, their threat range increases by 1. This ability stacks with the Improved Critical feat and the keen enchantment only. If you don’t want to get murdered by the DM, the polite thing to do is apply this threat range increase after the doubling effect.
Critical Strike spell (Complete Adventurer) As a swift action, you gain 1d6 damage, double your weapon’s critical threat range (as Keen Edge) and gain a +4 bonus to confirm critical hits. Not bad for a first level spell, and handy for those who just want to dabble in the fine art of fishing for crits.
Andras, the Grey Knight (Tome of Magic) Andras’ Sure Blows power grants you the benefit of the Improved Critical feat with any weapon that you can wield. If you already have the Improved Critical feat with a specific weapon, this ability gives you a +4 bonus to confirm the critical hit.
Divine Monk (Forgotten Realms - Faiths and Pantheons) If you somehow ascend to godhood, this ability grants your Monk character the keen, lawful, and vorpal qualities in addition to a few other abilities.
Divine Weapon Mastery (Forgotten Realms - Faiths and Pantheons) A character with this particular divine ability gains the benefits of Weapon Focus, Weapon Specialization, and Improved Critical with any simple and martial weapons that they wield.
Impact (Magic Item Compendium) This enchantment functions as the keen weapon enchantment, however it only affects bludgeoning weapons.
Dolorous Blow (Spell Compendium) This 3rd-level spell doubles the threat range of any weapon affected by it and automatically confirms any critical hits rolled by the affected weapon. The increased threat range does not stack with any similar effects, and the automatic confirmation effect does not stack with any other spells that affect critical hits. This spell cannot be used on a natural weapon.
Jagged Tooth (Spell Compendium) This Ranger and Druid spell doubles the threat range of one natural weapon, selected by the caster. This spell does not stack with any other effect that increases critical threat range.
Thayan Gladiator 2 (Forgotten Realms - Champions of Ruin) At the second level of this prestige class, you gain the benefit of the Improved Critical feat with the natural weapon you selected for your Improved Natural Attack at the first level.
Sakkratar’s Triple Strike (Forgotten Realms - Lost Empires of Faerun) This fifth level sorcerer/wizard spell grants the designated targets the ability to make two additional attacks on their full attack action for the duration of the spell. However, what we care about is that the weapons of anyone affected by this spell gains the keen and flaming burst properties for the duration of the spell.
Keen Strike feat (Epic Level Handbook) The user’s unarmed strikes become slashing keen weapons, with a 19-20 threat range.
Favored Critical feat (Masters of the Wild) 3.0 Material When character with this feat makes an attack roll against a favored enemy, the threat range of their weapon is doubled. This feat explicitly stacks with the keen weapon enchantment, but not the Improved Critical feat.
Power Critical feat (Masters of the Wild) 3.0 Material Once per day, if the user of this feat has the Improved Critical feat, they may automatically declare a single attack to be a critical threat. It must still be confirmed however.
Weapon of Impact spell (Forgotten Realms - Magic of Faerun) This spell functions as keen edge but for Bludgeoning weapons.
Incarnum Weapon spell (Magic of Incarnum) This spell manifests an independent weapon that attacks enemies independent of the caster. This weapon does not gain any benefit from your own feats or class features, however each point of essentia that the user invests in the spell increases the threat range of the weapon by one.
Hero’s Blade spell (Eberron Campaign Setting) This spell doubles your weapon’s critical threat range as per the Keen Edge spell, and explicitly does not stack with that spell nor the keen enchantment for weapons. However, it is called out as stacking with Improved Critical and provides a whole host of critical hit-related abilities, so expect this spell to show up quite a few times in this handbook!
Shifter Savagery feat (Eberron - Races of Eberron) This feats doubles the threat range of all your natural weapons and increases your damage dice by two size categories. Unfortunately, it only functions if you are a Shifter(Were-Touched) and are Raging as the Barbarian ability.
Bloodlust (Eberron - Forge of War) This shield enchantment can cast keen edge on a single weapon you carry once per day.
Gloves of Deadly Casting (Eberron - Forge of War) These gloves double the threat range of any ray and touch spells that the user casts. Explicitly does not stack with the Improved Critical feat.
Green Hunter 6 (Dragon Magazine 295) At sixth level, this prestige class gives you Improved Critical (Spiked Gauntlet)
Brawler 2 (Dragon Magazine 295) From 2nd level, this PrC is able to select Improved Critical (Improvised Weapons) (among other Weapon Focus-ish feats).
Acolyte of the Fist 7 (Dragon Magazine 296) At 7th level, this PrC gets Improved Critical (Unarmed Strike).
Vengeance Sworn (Dragon Magazine 296) At 10th level, this PrC’s critical threat range is doubled when it makes attacks against a creature of the dragon type. Explicitly stacks with Improved Critical and keen.
Orc Blademaster 4 (Dragon Magazine 299) At 4th level in this PrC, the character adds +1 to their critical threat range with a bastard sword. This stacks with any other sources of extended threat range, but this bonus must be added last.
Sniper (Dragon Magazine 310) This special ability of the Targeteer variant of the Fighter allows the user to sacrifice their iterative attacks from their Full Attack routine in order to increase the base threat range of their weapon by 1 for each attack they give up. It is important to note that a character cannot give up all of their attacks to fuel this ability, they still need to make at least one attack roll.
Shark Cultist 8 (Dragon Magazine 315) At 8th level of this hilarious PrC out of Taladas in Dragonlance, a Shark Cultist gets Improved Critical (Sharktooth Gauntlet) and Improved Critical (Bite) where the bite comes from a natural attack or a natural attack accessed via Wild Shape or similar.
Shen 4 (Snake Variant) (Dragon Magazine 319) At 4th level in this monk-ish PrC, a Shen of the Snake school gains Improved Critical (Unarmed Strike).
Bowman Charger (Dragon Magazine 325) At 9th level of this mounted-archery based PrC, the character gains Improved Critical (Composite Shortbow).
Huma’s Legacy spell (Dragonlance - Holy Orders of the Stars) Similar to Hero’s Blade above, this spell grants the benefits of the keen enchantment in addition to numerous other critical hit-related benefits that stacks with the Improved Critical feat but not the keen ability or the keen edge spell.
Gladiator 10 (Kingdoms of Kalamar - Player’s Guide) At 10th level, the gladiator base class receives the Critical Focus ability. While the gladiator is facing only a single opponent, their critical threat range is doubled (does not stack with anything else) and their critical damage multiplier is increased by 1.
Glaive of Azharadian 5 (Dragon Magazine 293) 1/day wielder can apply keen quality to a longsword or battleaxe for class level/rounds, does not stack
Mauling Gauntlets soulmeld(Magic of Incarnum) While bound to the Arms chakra, these soulmeld doubles the threat range of any melee weapon wielded by the user. Does not stack with any other ability that increases critical threat range.
Wintervein Dwarves affiliation (Player’s Handbook II) With an affiliation score of 30 or higher, a character automatically gains the Improved Critical feat for the Dwarven Waraxe and Dwarven Urgrosh as bonus feats.
Serrated weapon quality (Mercenaries by Alderac Entertainment Group) Third-Party Content This non-magical weapon quality increases a weapon’s critical threat range by 1 for 300 gp. This is separate from the Masterwork quality and it does not stack with any other improvements to the critical threat range.
Psychic Weapon Master 7 (The Mind’s Eye Archives) At seventh level, the Psychic Weapon Master gains the Psionic Critical ability, which gives them the Improved Critical feat with their specified weapon for free. If the Psychic Weapon Master already has the Improved Critical feat, this ability instead increases their critical threat range by 2 (and though it isn’t specified, the polite thing to do is apply this bonus after the effect of Improved Critical, lest the dread Rocks Fall occurs.)
Weapon Master 7 (Oriental Adventures) Like the psionic version above, at 7th level, the Kensei weapon master gains Improved Critical as a bonus feat, and again, if they already have the feat, they get a +2 bonus to their threat range (which is specifically stated to be applied last.)