There's no way around it, the achievements for this game are going to be a several-hours-long, tedious grind. Luckily however, there are a few things you can do to help make it go a little bit faster.

I have listed the achievements in order of difficulty for the most part, and most of them are pretty straightforward, so if you're looking for tips on the harder/grindier ones you should probably skip right to "Specialty achievements" section.

Let's begin!

A few things that should be addressed right off the bat. For the purposes of completing these achievements there are a couple of gameplay tips and console commands that will help immensely.

First off, DO NOT EVER "LOAD" A GAME. Always start by selecting New Game and choosing your difficulty level. Not sure if it's a bug or what, but attempting to load a previous save will wipe out all of your progress including your headcrab kill count! You have been warned!!!

Next, don't even bother trying to get beyond wave 15 or so. If you're more concerned with trying to set a new high score, then by all means go for it, but for grinding achievements it's more of a waste of time than it's worth. The headcrabs at this point become too strong and you'll just waste a lot of unnecessary time whacking away at them for each kill. You are much better off to just suicide or let yourself be killed and starting fresh again with weaker headcrabs.

How to suicide? Bind a key to the "kill" command using the in-game console. Simply open the console using the tilde `~ key by default and type "bind (your key) kill" without any quotes. So, if you want to bind it to K, you would type: bind k kill

This is useful for ending rounds once you've gotten to the point where the headcrabs are becoming too strong and time consuming to kill. It also works well for the Veteran achievement as described in the "Specialty achievements" section below.

Another command that can help, typing "+attack" in the console will make you swing the crowbar endlessly. Since you're going to be using the crowbar non-stop anyways, this command can help with finger fatigue. For some reason binding this to a key doesn't work; you'll have to do it manually every time. Type "-attack" in the console to disable it again. (Edit 9-2-2018: see comment section for Nero's explanation how to bind this command to a toggle key!)

Finally, last but most important: corners are your friend. Don't try and be cute. Don't try and be fancy. Just tuck your butt in a corner and spam that crowbar!

Many of the achievements for this game are "story mode" related, meaning you'll earn them just through general gameplay. The ones below are pretty much impossible not to get. Just play through at least 8 waves in each level and you're done.



Ladder Completed - Survive all 8 "Ladder" waves.



HCF_Killbox



HCF_Dungeon



HCF_Labmoar



HCF_Temple



HCF_Factory



HCF_Range

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Headcrab Frenzy! Spend 60 minutes in Frenzy mode.



Survivor - Regenerate 100,000 health points.



Jinxed - Miss 1000 times.

These last three will also unlock in general long before you've gotten to the last achievement, but they will take a considerable amount of time.

If for some reason you want to speed up the process, you can hasten the Frenzy achievement by using it counter-intuitively - activate it when there are no headcrabs around between waves and let it slowly burn off. Attacking enemies actually shortens the duration, so kite around and avoid swinging the crowbar until you've got a BIG pile of crabs in front of you.

Survivor can be hastened by letting headcrabs damage you and then, again, kiting around while your health regenerates. The more damage you can take and then recover, the better. Using the health regen pickup obviously helps immensely with this process. Still not really worth the effort though, tbh.

Jinxed is the biggest pain in the butt of all of these because there is no way to force it or quicken the process. It only works when attacking ethereal (ghost) headcrabs which will randomly cause you to "miss," so you don't really have much choice but to just let this one come naturally.

These are the achievements for completing each difficulty level. They're similar to the ones above except that you need to do each one again at least once on every difficulty.



Headcrab Expert - Beat the game on "Easy" skill level.



Headcrab Connoisseur - Beat the game on "Medium" skill level.



Headcrab God - Beat the game on "Hard" skill level.

Pretty straightforward. These should be pretty easy for most people, but it you're struggling for some reason on the harder levels then you might consider using god or notarget (just type those cvars into the console). The game has sv_cheats enabled by default so don't worry about it affecting your ability to earn achievements.

Ok, now we can get into the meaty achievements. You may get lucky and unlock some of these through normal gameplay but most will require at least a bit of effort to make that happen.



Ladder Master - Survive 20 waves in "Ladder" game mode.



Random Master - Survive 20 waves in "Random" game mode.



Beyond Godlike - Perform a 25x combo



High Score! - Score 1,000,000 points in a single match.

All of the above can be pretty easily achieved by playing each game mode (Ladder, Random) on the first level, HCF_Killbox on Easy, and simply crouching in a corner and spamming the crowbar. Keep an eye on your pickups (Invisibility, Health Regen, Lightning, Invulnerability) and grab them when you can. When they run out, don't forget to use Frenzy!

For an alternative method for Ladder Master and Random Master, you can refer to Berserkr's guide found here, but note this will not work for Beyond Godlike or High Score!

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Artistic Confusion - Cause some disorder in the Museum.

The Museum can be reached in the level select hub. It's the door right in the center, the only one that doesn't have a portal in front of it. Like the achievement description implies - get in there and cause some mayhem!

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Nice Catcher - Perform 250 nice catches.

This is best explained by Cos from his guide over on Astats:[astats.astats.nl]

Nice catches are environmental kills. I suggest the HCF_Labmoar arena for this.

Invulnerability repeatedly spawns at the center of the arena, under the fatal energy leak. Picking it up and then remaining in that place for a while will net you a good amount of kills as the headcrabs swarm at you and get gibbed by the energy. Get out before it wears off and strafejump around the arena until it respawns and repeat the process.

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Nimble on Feet - Don't be bitten at all during a single wave.



Sniper - Shoot 500 headcrabs using firearms.

Both of these achievements can be easily earned in HCF_Range (required for Sniper). Start the level on Easy, Ladder mode, then kite around the edge of the map and use the turrets to shoot the first wave of normal headcrabs.. Rinse and repeat for through the next multiple waves for Sniper.

For an alternative to Nimble, you can again use Berserkr's guide and use that same location to hide from the headcrabs and spam the crowbar until the first wave is gone. This method requires a bit of luck though since sometimes a headcrab will still manage to damage you.

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Veteran - Win 50 matches.

It took me a while to figure out what constitutes a "match" in this game, since there is no end and no win-state. Turns out that every start of a map is considered a match "win," even if you don't make it past the first wave. So just start any map 50 times and you're done.

To make this grind a little quicker you can use the "kill" console command addressed in the "General tips" section above. Start any map and then just keep spamming that key to suicide yourself and restart the level over and over again. A good while and 250 deaths later the achievement should be yours.

These are the kill-count achievements, the most time consuming and tedious of all. Even after you have all the others completed you'll probably still have most of these left to go. Although the purpose of this guide is to make them slightly less time consuming, you should still count on spending at least another hour or more finishing these up.



Terminator - Exterminate 1500 normal headcrabs.



Assassin - Exterminate 2000 fast headcrabs.



Fireman - Exterminate 2500 fire headcrabs.



Antidote - Exterminate 3000 poison headcrabs.



Melter - Exterminate 3500 ice headcrabs.



Insulator - Exterminate 4000 electric headcrabs.



Exorcist - Exterminate 4500 ghost headcrabs.



Psycho - Exterminate 5000 hallucinagenic headcrabs.

My recommendation is to stick to Ladder mode, Easy difficulty until you've earned at least Terminator, Assassin, Fireman, and Melter. After that, switch over to Random mode, Easy difficulty.

The reason for the switch at this point is because you're going to waste far too much time going through all those lower-tier waves in Ladder just to reach the higher-tier headcrabs we need for the last four achievements. Also, Random spawns more high-tier headcrabs per round than you would have earned by their respective wave in Ladder anyways.

To put it another way, reaching the hallucinagenic headcrab level in Ladder would give you 100 kills toward the Psycho achievement, but in Random you should easily have over 200 Psycho kills by the time you get to that same level. (there are often 12-30 hallucinagenic crabs per wave)

Now just keep doing what you've been doing all along (corner crouching, suicide by round 15) and you should be getting close to 250 kills for each crab type by every 15th wave. With the headstart you got from Ladder mode you should be able to finish this final achievement up in no time.

And that's it. Hope this guide made it a little bit quicker and easier for you!