Complete the Hazard Course
Start the game
Get the HEV suit
Grab the battery in your locker
Find the small cup
Speak to all scientists in the pre-disaster maps
Do the microwave thing
Play with the laptop in the entrance area
Press the alarm button in the entrance area
Turn off the lights in the office in the starting area
Get the crowbar
Make the hanging scientist in the entrance area fall to their death
Get killed by the eletric ceiling light
Get killed by the fan in the vents
Fail to save the "we're doomed" scientist
Save the "we're doomed" scientist
Complete We've Got Hostiles without activating any laser traps or trip mines
Fly directly into the pipe from the train
Blow up all the bridges in Blast Pit
Use the broken elevator
Solve the Blast Pit fan puzzle
Never get noticed by the tentacles
Fry the Gargantua
Drive a train
Launch the satellite rocket
Save the barney from running into the barnacle
Repeat the conveyor loop
Kill all the aliens with all the experiments
Kill a soldier with an experiment
Kill a barney or scientist with an experiment
Kill a scientist with the instruments
Reach the cliffs
Surface behind the tank
Explode the Gargantua with airstrikes
Reach Xen
Meet the Nihilanth
Beat the Nihilanth
Get teleported to all of Nihilanth's spaces
Face the G-Man
Join the G-Man
Don't join the G-Man
Drink a soda can
Throw a gib at a scientist or barney
Pick up an alien gib
Hit a headcrab with a melee attack in mid-air
Don't kill any scientist or barney the entire game
Get sniped
Touch a houndeye without hurting it
Push or lure a scientist into a barnacle
Jump out of the intro train
Try to use the trash compactors as trains
Get the "Bothersome", "Important Messages", "Trouble", "Magnusson Experiment", and "Lights Out!" achievements
Hold cup in front of Kleiner
Skip the whole "We've Got Hostiles" chapter
Skip the whole "Power Up" chapter
Complete "On A Rail" without ever using a train
Gain more than 1000 HP from a negative damage door
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