Sink the Horror Electric
Complete Quake Episode 1: Dimension of the Doomed in single player.
Bottom of the Well
Complete Quake Episode 2: The Realm of Black Magic in single player.
Beneath the Blue Chambers
Complete Quake Episode 3: The Netherworld in single player.
The Last Unexplored Path
Complete Quake Episode 4: The Elder World in single player.
Indigestion
Defeat Shub-Niggurath in single player.
Gateway Traveller
Complete Scourge of Armagon Episode 1: Fortress of the Dead in single player.
Dominated Dominion
Complete Scourge of Armagon Episode 2: Dominion of Darkness in single player.
Arma-gone
Complete Scourge of Armagon Episode 3: The Rift in single player.
Overlord Overdone
Complete Dissolution of Eternity Episode 1: Hell's Fortress in single player.
Dragonslayer
Complete Dissolution of Eternity Episode 2: The Corridors of Time in single player.
The Year Zero
Complete Dimension of the Past in single player.
Vengeance Denied
Complete Dimension of the Machine in single player.
Vertical Vengeance
Find the secret exit in Quake Episode 1: Dimension of the Doomed.
Nevermore
Find the secret exit in Quake Episode 2: The Realm of Black Magic.
The Hot And Winding Road
Find the secret exit in Quake Episode 3: The Netherworld.
Into Sandy's City
Find the secret exit in Quake Episode 4: The Elder World.
Military Complex
Find the secret exit in Scourge of Armagon Episode 1: Fortress of the Dead.
The Gremlin's Domain
Find the secret exit in Scourge of Armagon Episode 2: Dominion of Darkness.
A Long Yard
Find the secret exit in Scourge of Armagon Episode 3: The Rift.
The House of Doom
Find the secret exit in Dimension of the Past.
Sandy's Room
Find the secret exit in Dimension of the Machine.
Secret Sleuth
Find a secret area.
The Well of Wishes
Find the Well of Wishes in the Crypt of Decay.
You're not supposed to be here!
Find the secret message in Tur Torment.
Friendly Fire
Kill a monster with another monster's attack.
Discharge
In deathmatch, electrocute an enemy in water without dying.
The Shambler Dance
Kill a shambler before it is able to cast its lightning attack.
A Close Shave
Kill a shambler with an axe.
The Painless Maze
Complete E4M6: The Pain Maze on Nightmare without taking damage.
Slipgate Pacifist
Complete E1M1: The Slipgate Complex on Nightmare without firing a shot.
Shub's Bud
Complete Quake on Nightmare in single player.
Scourge Done Slick
Complete Scourge of Armagon on Nightmare in single player.
Rogue Ranger
Complete Dissolution of Eternity on Nightmare in single player.
Otherworldly
Complete Dimension of the Past on Nightmare in single player.
Machinehead
Complete Dimension of the Machine on Nightmare in single player.