Superior slayer monsters are more powerful monsters than their normal slayer monster. They can only be fought when you have the "Bigger Badder" slayer ability unlocked. Speak to any slayer master, and see their learn shop to purchase this ability.
A superior can only spawn on slayer task. They spawn upon defeating a slayer monster. However not all monsters have a superior version.
Like the Bigger Badder Ability, there's a similar ability for boss tasks called the "Superior Fury". Once learned, while on boss tasks bosses will be able to spawn their superior version. Speak to Hanto, the boss master at the Slayer camp.
Superior Rate Multipliers
There are ways to increase the chance for a superior to spawn. Here's all the available methods to increase your chance.
Superior Chance Increases
Where to obtain
Location
% Increase
Well of Goodwill
West of Home
10%
Superior Wednesday
None
15%
Bigger Badder 2 Ability
Slayer Learn Shop
5% (Permanent)
Adventurer's Book
Quest tab
1% (Permanent)
Boss Superior Rate Multipliers
You may increase the chance to spawn a boss superior through various methods. Here are all the current available methods
Boss Superior Chance Increase
Where to Obtain
Location
% Increase
Overdrive Ability
Hanto's Learn Shop
5%
Superior Monsters
Here's a list of superior monsters, their rates and from which slayer master you can receive them.
List of Monster names, Spawn Rate and Slayer Master.
Monster Name
Spawn Rate
Slayer Master
Pyrefiend
1/250
Mazchna, Vannaka
Aberrant Spectre
1/250
Vannaka
Basilisk
1/250
Vannaka
Cave Horror
1/250
Vannaka
Jelly
1/250
Vannaka
Turoth
1/250
Vannaka
Bloodveld
1/250
Vannaka, Chaeldar
Jungle Horror
1/250
Vannaka, Chaeldar
Otherworldly Being
1/250
Vannaka, Chaeldar
Dust Devil
1/250
Vannaka, Chaeldar
Jungle Strykewyrm
1/250
Vannaka, Chaeldar
Infernal Spider
1/200
Vannaka, Chaeldar
Infernal Mage
1/250
Chaeldar
Nechryael
1/250, 1/150
Chaeldar, Sumona
Kurask
1/250, 1/150
Chaeldar, Sumona
Desert Strykewyrm
1/250, 1/150
Chaeldar, Sumona
Chilly Hand
1/250, 1/150
Chaeldar, Sumona
Dark Celestial
1/250, 1/150
Chaeldar, Sumona
Magma Elemental
1/250, 1/150
Chaeldar, Sumona
Magma Torcher
1/250, 1/150
Chaeldar, Sumona
Magma Beast
1/250, 1/150, 1/100
Chaeldar, Sumona, Kuradal
Lichwood Stag
1/250, 1/150, 1/100
Chaeldar, Sumona, Kuradal
Grovewarden Snake
1/250, 1/150, 1/100
Chaeldar, Sumona, Kuradal
Loreroot Fungal
1/250, 1/150, 1/100
Chaeldar, Sumona, Kuradal
Gargoyle
1/250, 1/150, 1/100
Chaeldar, Sumona, Kuradal
Abyssal Demon
1/150, 1/100
Sumona, Kuradal
Abyssal Horror
1/150, 1/100
Sumona, Kuradal
Ice Strykewyrm
1/150, 1/100
Sumona, Kuradal
Shadow Demon
1/150, 1/100
Sumona, Kuradal
Dravonic Demon
1/150, 1/100
Sumona, Kuradal
Dravonic Devil
1/150, 1/100
Sumona, Kuradal
Dravonic Hydra
1/150, 1/100
Sumona, Kuradal
Fire Dragon
1/150, 1/100
Sumona, Kuradal
Infernal Demon
1/150, 1/100
Sumona, Kuradal
Balrog
1/150, 1/100
Sumona, Kuradal
Dark Beast
1/100
Kuradal
Tormented Beast
1/100
Kuradal
Crystalite Gargoyle
1/100
Kuradal
Ebonchill Dragon
1/100
Kuradal
Ebonchill Starlight
1/100
Kuradal
Dark Matter Demon
1/100
Kuradal
Dark Matter Gorak
1/100
Kuradal
Boss Superiors
Here's a list of boss superiors that you may obtain as a task and their spawn rate. Boss tasks can only be received as a task from Hanto, the boss master.