I'll be going through all of the unmissable story achievements first, and then get into the more nuanced achievements that you may need to be purposefully trying to get.
This guide is split into 2 parts. This is part 2.
Chapter - Highway 17
For this one you’ll need to pin a soldier to the billboard in the chapter “Highway 17.” Before coming up to the area with the combine at the billboard there is a hill with a crossbow on top. You can grab it here and then shoot the soldier to pin them to the billboard.
Chapter - Sandtraps
For this one you’ll need to cross the antlion beach without touching the sand in the chapter “Sandtraps.” For this one you’ll basically just need to go slowly and take any large flat items with you to use as platforms and bridges while going through. The part of the video guide where I show a sped-up version of this is here.
Chapter - Nova Prospekt
For this one you’ll need to kill 50 enemies by controlling antlions. After killing the first large antlion you’ll be given the ability to use pheropods to control antlions. You’ll then go up to and into Nova Prospekt and can sit back, use the pods, and kill the soldiers using these. Doing that you’ll eventually get the achievement.
For this one you’ll need to kill an enemy with a toilet. There are multiple chapters where this could be done, but you basically just need to pick one up with a gravity gun and shoot it at an enemy to kill them.
For this one you’ll need to kill 5 enemies using manhacks. There are also multiple chapters that you can do this on. You’ll need to grab the manhacks with your gravity gun and either run up to the combine soldiers or just shoot it at them to kill them.
Chapter - Follow Freeman
For this one you’ll need to kill all of the snipers in City 17. There are 5 snipers you’ll have to kill that are sitting in blacked out windows on the chapter “Follow Freeman.” You can use rockets or grenades to get this done.
Chapter - Our Benefactors
For this one you’ll need to disintegrate 15 soldiers by throwing them into a combine ball field. Once on the chapter “Our Benefactors” your gravity gun will be upgraded and you can start picking up enemies and putting them into these large energy ball fields. Do this as much as you can and you’ll get this achievement pretty quickly.
This one is for finding all 45 of the Lambda caches in Half-life 2. I made a separate video going over all of these here.
For this one you’ll need to destroy six gunships during your play-through. As long as you destroy most that you come across you’ll eventually get this. Any time you see a large ammo box of rockets chances are there will be some gunships around for you to destroy.
And there you go! 100% of the achievements in Half-Life 2. If you found the written guide helpful be sure to like/favorite it and drop a comment down below.
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I also cover the achievement/trophy guides for many other games so whether it's on Youtube, our website, or Steam check out some of my other guides to help you 100% more games.
Thanks for reading/watching!
