Portal Tips and Tricks
Each entry below is one mechanic, what it costs you, and the update it was last checked against. Filter by category or difficulty to narrow the list, and use the anchor beside any heading to link straight to a single tip.
Advanced Maps
#Advanced chamber turrets are caged and cannot be touched
They still shoot, but you cannot pick them up, knock them over, or portal them away, which removes every standard turret answer at once. The cubes are not reduced in these maps, so using one for cover stops being a fallback and becomes the intended solution.
Verified on March 2010 ARG update
Turrets
#What disables a turret is tipping it over, not touching it
A bump that fails to topple achieves nothing at all. Picking one up from behind and dropping it awkwardly works, so does knocking it with a cube, shooting a portal at its feet, or steering a High Energy Pellet into it. You never need to destroy one.
Verified on March 2010 ARG update
Falling
#Portal has no fall damage at any height whatsoever
Chell's Advanced Knee Replacement absorbs everything up to terminal velocity, so you can drop from anywhere onto solid ground and walk away. The game needs you falling into portals without hesitating, which makes gravity a tool here rather than a hazard.
Verified on March 2010 ARG update
Least Steps
#Cancel the exit portal mid-flight so the landing costs no step
A fast landing registers as a step, so travel through floor portals and close the exit while you are still airborne to come down slowly. Throw cubes to their buttons rather than carrying them, and quick-save constantly, since the counters rewind with the save.
Verified on March 2010 ARG update
Movement
#Mid-air steering is free and cannot shorten a fling
The Source engine's air acceleration only ever adds velocity, and it applies no friction at all while you are off the ground. Holding a direction to nudge your landing point costs you nothing, which is exactly what the tighter advanced chambers ask for.
Verified on March 2010 ARG update
Movement Tech
#Classic Source bunny hopping does not work in Portal
The speed-chaining bhop was removed from the Orange Box engine this game runs on, which is precisely why the community reached for Accelerated Back Hopping instead. Muscle memory from Half-Life 2 or Counter-Strike will not transfer here.
Verified on March 2010 ARG update
#The speed cap is measured against where you are looking
Turn 180 degrees and hop backwards and the engine accelerates you instead of slowing you, roughly doubling your speed each hop. Hold neither forward nor back while doing it. Accelerated Back Hopping is a speedrun tool and is never needed for normal play.
Verified on March 2010 ARG update
GLaDOS Fight
#The neurotoxin countdown runs six minutes, and it starts late
It only begins once you have burned the first core, and GLaDOS never states a duration out loud. The clock you are watching is on the wall monitors, so find one early. Her line about the next couple of minutes comes after the second core and is a taunt, not a timer.
Verified on March 2010 ARG update
Achievements
#Camera Shy resets the moment you skip or replay a chamber
All 33 have to come in one continuous playthrough, and the counter does not carry across playthroughs. Delete old local saves and clear Steam Cloud before you start, because a stale save holding a bad count is the other common way this run never finishes.
Verified on March 2010 ARG update
#Finding a radio is only half of it, the light has to turn green
Each one must be carried to its signal coordinates until the indicator goes from red to green and the static resolves into a Morse or SSTV transmission. Collecting all 26 and never moving them is the single most common way this achievement stalls.
Verified on March 2010 ARG update
Bonus Maps
#Bonus maps open as you clear chambers, not after the credits
Each advanced and challenge chamber appears under Bonus Maps the moment you finish the matching Test Chamber in the campaign, so there is no need to complete the game first. Developer commentary is the one thing that genuinely waits for the ending.
Verified on March 2010 ARG update
Challenge Maps
#Not one Gold medal requires Accelerated Back Hopping
Chamber 14's 0:10 Gold comes from the two-portal fling shortcut and Chamber 18's 1:13 from cube-shield routing. Plain constant jumping is the standard time advice, so learning the engine exploit first is effort spent on the wrong problem.
Verified on March 2010 ARG update
Collectibles
#The radios are not one per chamber, so do not count as you go
Most chambers hold one, but Chamber 15 has two and Chamber 18 has three. Chamber 00 is the one people skip entirely, since its radio sits in the relaxation vault right at the start before the game has taught you to look for anything.
Verified on March 2010 ARG update
#Half the Rat Man dens are back in the test chambers
Six exist in total. The first three sit behind wall panels in Test Chambers 16, 17, and 18, and the remaining three are in Chamber 19. Searching only the maintenance areas during the escape means missing every single one of them.
Verified on March 2010 ARG update
Commentary
#No achievement unlocks while developer commentary is running
A commentary playthrough will not pick up anything you still need, so do it after the list is clean rather than alongside it. Some nodes also change the visuals or briefly take your viewpoint, which makes it less passive than an audio track.
Verified on March 2010 ARG update
Advanced Maps
#The Chamber 14 fling shortcut was removed from the advanced map
Valve made the relevant floor portal-proof there. The famous two-portal route onto the exit lift belongs to the normal and challenge versions, where it is the Gold solution for Least Portals, so hunting for it in the advanced chamber wastes your time.
Verified on March 2010 ARG update
Least Steps
#A step is a discrete footfall, so standing still is free
Placing portals and moving cubes cost nothing at all. Landings only register above a speed threshold, and every mid-move correction adds one. Jumping is not free either, which is why the efficient pattern is alternating a step and a hop.
Verified on March 2010 ARG update
Lore
#The name Doug Rattmann appears nowhere in the 2007 game
The string drattmann first showed up as a BBS login during the 2010 ARG, and the full name and backstory arrived with the Lab Rat comic in 2011. Most of what gets attributed to the dens, including his illness and his interest in Chell, is the comic's.
Verified on March 2010 ARG update
Platforms
#The Xbox 360 and PS3 releases have no radios at all
Neither ever received the March 2010 ARG update, so they carry 14 of the 15 achievements and still run the original 2007 ending. Transmission Received is the one that does not exist there, not Camera Shy or any of the challenge medals people usually name.
Verified on March 2010 ARG update
Test Chambers
#The pellet room only accepts portals in its top half
Valve restricted the lower surfaces deliberately. If a portal refuses to stick where you are certain it should, that is the reason rather than a bad shot, and no amount of repositioning will change it.
Verified on March 2010 ARG update
What to Read Next
- Puzzle Mechanics. Portals, flings, turrets, and the engine behavior behind every movement trick here.
- Advanced Maps and Challenges. All 18 advanced chambers plus the medal rules for steps, portals, and time.
- 100% Achievement Guide. All 15, including the radio hunt and the one that resets if you replay a chamber.
- Test Chamber Walkthrough. Every chamber, the escape, and the GLaDOS fight.
- Lore and ARG History. The 2010 radio ARG, the Rat Man dens, and what the game itself never says.
- Getting Started. Controls and the first chambers, if you are starting today.