Watch a speedrunner fly and surf through Half-Life 2's water levels without an airboat

It’s possible to ignore the boat almost entirely in Half-Life 2’s first notorious vehicle level, and speedrunner Woobly demonstrated it last night during his Summer Games Done Quick run of the classic FPS. Dubbed Boatless by the HL2 speedrunning community, the strategy isn’t exactly new, but for those who only hear about speedruns when the Games Done Quick carnival rolls into town and hate the Water Hazard chapter, it’s a revelation. 

A few tricks go into making the run possible, the most important of which is save deletion. It’s a method of creating and deleting saves to reset Freeman’s weapon inventory and health. Since most of Water Hazard’s water is, well, a hazard, it’s nearly impossible to swoop through the radioactive liquid without marooning yourself eventually. With save deletion, runners can just save, delete the save, and die to get healthy again. It will also spawn the boat nearby, no matter where the runner leaves it behind. 

Before save deletion was discovered, the run wasn’t possible even if players somehow survived the ordeal. Throughout the entire level, there’s a single trigger that requires the boat, and it’s right at the end. Gordon doesn’t have to even be there. Save deletion lets runners spawn the boat right at the end when it’s needed, so some NPCs can talk to it and open a gate. 

But to swoop around like a damn bird on a surfboard and fly over most of the map, runners use variations well known Source exploit to gain speed called accelerated back hopping. To do it, you need to jump forward, turn around in the air, and jump right when you land. The Source Runs wiki explains how this process actually gains speed: 

“When you exceed the game's speed limit, the game tries to slows you down whenever you jump, back to the desired speed. By default the game thinks that you're moving forwards, so when you exceed the speed limit, it'll accelerate you backwards. If you are facing backwards, this will only increase your speed. So, the faster you're going, the more you will get accelerated.”

By gaining speed and hitting certain surfaces at angles that don’t trigger damage, runners can treat level geometry like a stunt course. It’s just like real life, basically. 

As impressive as Woobly’s SGDQ run is, it’s nothing compared to the World Record run by Rainnt, set just under a month ago. To see their near perfect Boatless run, skip to the 20-minute mark or so.