Half-Life 2 Difficulty: What Easy, Normal and Hard Change

Half-Life 2's menu describes Hard like this: "Enemies are very tough; your weapons are less effective." Hold that first half up to the code and it mostly falls apart. A Combine soldier has 50 health on Easy, 50 on Normal and 50 on Hard. For nearly everything you fight, what changes is you: how hard you hit, how hard you get hit, and how much ammo is in the box on the floor.

This vertical's beginner's guide gives the difficulty choice a passing mention, and the weapons guide lists damage numbers at Normal without saying what the setting does to them. This is the rest of it: the multipliers, the enemies that carry their own special rules, and the five kinds of damage the setting leaves alone.

Valve wrote Normal and did maths for the rest

The design decision behind all of this sits in a short comment in Valve's game code. Half-Life 2, it says, "only uses one skill config file" — the Normal one — and "synthesizes" Easy and Hard from it. (Valve's code calls the middle setting Medium, skill level 2. This guide uses Normal, the word in that setting's own menu description.)

That config file, skill.cfg, holds most of the game's Normal numbers: 10 damage for a crowbar swing, 5 for a pistol round, 50 health for a Combine soldier, 500 for an Antlion Guard. Easy and Hard never get their own copy. They are produced by a handful of multipliers in the game rules, plus a short list of enemies that carry their own hard-coded exceptions.

Every number in the tables below is read from, or worked out from, the Half-Life 2 game code Valve published in its Source SDK 2013 in June 2013. The singleplayer code stayed in the public repository until Valve removed it on February 18, 2025, and it is still there in the history. One honest caveat: the code for the 20th Anniversary build is not public. Valve's update notes since November 2024 don't list a change to the difficulty scaling, but they do touch aim assist, which is flagged where it matters.

The whole difference, in one table

Two lines in that table deserve a second look.

The menu says Easy is the setting where "the computer helps you aim." In the 2013 code, Normal gets the same autoaim at the same strength — both scale values are 1.0 — and only Hard switches it off. The 20th Anniversary Update then added separate Aim-Assist settings for mouse and gamepad, and Valve's notes don't say whether Hard still disables them, so treat that row as the pre-2024 behaviour.

And the regeneration row only covers the allies Valve's code marks as vital, such as Alyx, Barney and Father Grigori. Your rank-and-file rebel squad does not regenerate on any setting.

What the setting does to your guns

The damage multiplier is applied to your bullets, crowbar swings, crossbow bolts and the explosions you set off, whenever the target is an NPC. Crates and other breakables are deliberately left out — Valve's comment says it's there so they don't get easier or harder to break on different settings. Here is what 150%, 100% and 75% do to a standard 50-health Combine soldier, counting body hits:

Three results worth carrying into a fight:

• On Easy, the .357 kills a soldier with one body shot. 40 becomes 60. On Normal and Hard it is two.
• On Hard, a point-blank shotgun blast with every pellet on target no longer kills a soldier. Seven pellets at 6 damage is 42, eight short. The double-barrel secondary (12 pellets, 72 on Hard) still does it in one.
• The crossbow one-shots soldiers on every setting, and the white-armoured Elites too: their 70 health is still under the crossbow's 75 on Hard.

Headshots are the cheapest way to claw back Hard's penalty — Valve's code gives Combine soldiers double damage to the head on every setting.

Headcrabs ignore the multiplier for melee entirely. Valve's headcrab code has a rule commented "Certain death from melee bludgeon weapons!" — any crowbar hit kills a headcrab outright, whatever its health. That covers all three types, including the 35-health poison headcrab, on Easy, Normal and Hard alike.

Thrown objects dodge the Hard penalty

This is the most useful thing in the code, and the menu never mentions it. The skill adjustment is wired into the bullet, melee, crossbow bolt and explosion code. Physics impacts never pass through it. A sawblade, radiator or cinder block you launch with the gravity gun hits exactly as hard on Hard as it does on Normal.

So Hard doesn't just make the game harder. It tilts it toward physics. Your guns lose a quarter of their damage and your ammo boxes lose 40% of their contents, while the junk lying around the streets of Ravenholm keeps its full value as ammunition.

The Antlion Guard makes the point sharper. Its code carries a line commented "Hack to make antlion guard harder in HARD": on Hard it takes 75% of all damage that isn't a physics impact. That stacks with your own 75%, so your bullets and the grenades you throw land at roughly 56% of their Normal value. Thrown objects skip both cuts. The Guard only takes impact damage from objects the player threw, capped at 100 per hit on every setting. If you are fighting the Nova Prospekt Antlion Guards on Hard, the maths tips hard toward throwing: your guns and grenades lose about 44% of their punch against it, and a thrown prop loses none.

What hurts you, and what the setting cannot touch

Enemy attacks are scaled by the damage-taken multiplier. A few Normal values from skill.cfg, scaled:

Then there is the exemption list. Valve's code skips the multiplier for five damage types, with the comment "Skill level doesn't affect these types of damage":

1. Falling
2. Drowning
3. Crushing, which covers being hit by physics objects
4. Poison, the damage type of the poison headcrab's bite
5. Combine sniper rounds

Falls and sniper nests hit exactly as hard on Easy as they do on Hard. If you want to test your build rather than trust the table, open the developer console (the console commands guide covers turning it on) and type sk_dmg_take_scale3. The console prints the value your build uses for Hard.

Ammo: only the boxes shrink

The ammo multiplier lives in exactly one place in the code — the function that runs when you pick up an ammo box. It rounds down, and it never gives less than one of anything.

That floor matters more than it looks. Single-item pickups can't drop below one, so rockets, SMG grenades and energy balls come in at full rate on Hard. It's the bullet, shell and bolt economy that dries up.

Two more things the multiplier never touches: weapons you take off dead enemies, and the refillable ammo crates, such as the infinite RPG crates. Health kits, vials and suit batteries give the same amount on every setting. On Hard each one simply covers fewer hits.

Bosses and soldiers that change behaviour

A few enemies carry their own difficulty rules on top of the multipliers.

Combine squads throw more grenades on Hard. When a soldier in a squad falls back to cover on Hard, he throws a grenade on the way if he has a throw lined up and no squadmate is already throwing. On Easy and Normal, the same soldier just takes cover or charges. It's the clearest case of Hard changing how a firefight plays, not just how long it lasts.

Gunships die in fixed chunks. Every qualifying explosion takes one slice of health, and skill.cfg sets five slices. Easy halves that and rounds up; Hard multiplies it by 1.5 and rounds down:

Striders cost no extra rockets on Hard. Normal and Hard both take seven, because Valve set the rocket counts directly. Energy balls are different: each does a fixed 25 to a Strider, run through your damage multiplier and rounded down, against 350 health. That is where 10, 14 and 20 come from. Some wiki tables list lower counts. Combine OverWiki's own tactics section says energy balls do about half a rocket's damage, which is exactly what 25 against a 50-damage rocket gives you.

The Water Hazard Hunter-Chopper doesn't get tougher at all. In Half-Life 2 it only takes damage from the airboat gun and rockets. The airboat, not you, is recorded as the shooter of that mounted gun, so its rounds never pass through your damage multiplier. The dam fight takes the same amount of fire on all three settings — the vehicle chapters guide covers how to survive it. What does scale is the chopper's own gunfire and bombs coming the other way.

The Episodes play by harsher rules

Since the 20th Anniversary Update, Episode One and Episode Two sit in the Half-Life 2 main menu, and a few difficulty rules only come into play there:

• Hard costs you 200% damage taken, not 150%. The Episodes code sets it separately.
• Hunters are gentler on Easy. Each flechette volley fires 7 darts instead of 8, and Hunter charges and volleys come further apart.
• Energy balls stay in the gravity gun longer on Easy. A held ball dissolves after 8 seconds normally and 12 on Easy — Valve's comment says it's there to give players more time to aim.
• Antlion workers stop staggering their acid on Hard. On Easy and Normal, a worker's volley makes its squadmates hold fire for part of its flight. On Hard they don't wait.
• Episode Two's Hunter-Chopper dies to its own bombs thrown back with the gravity gun: 3 on Easy, 5 on Normal, 5 on Hard.

The episodes guide covers the fights themselves. The short version for difficulty: Hard in the Episodes is a bigger step up from Normal than Hard in Half-Life 2 is.

Changing difficulty mid-game

The difficulty is a single console variable, skill: 1 for Easy, 2 for Normal, 3 for Hard. You can set it from the Difficulty page in Options, or type skill 3 into the console. The game rules re-read it every frame, so a change takes effect immediately. No reload, no new game.

It costs you nothing either. None of Valve's achievement code for Half-Life 2 or either Episode checks the skill level, so the achievements guide plays the same on any setting. Zombie Chopper on Easy counts exactly as much as Zombie Chopper on Hard.

Which setting to play

First playthrough: Normal. The beginner's guide says the same, and the code backs it up. Normal is the setting the whole config file describes; Easy and Hard are mostly that file multiplied.

Replay: Hard, if you like the gravity gun. Hard's real cost is the 60% ammo boxes and the 75% guns, and the physics exemption means a thrown object never loses a point. Striders cost the same seven rockets they do on Normal. A Hard run is less "enemies got tougher" and more "stop shooting, start throwing".

Commentary or story run: Easy. At 150% damage out and 50% in, Easy triples the ratio of damage you deal to damage you take, and the 3.5-hour developer commentary track gets interrupted by far fewer deaths. Just don't expect Easy to save you from falls or sniper fire.

Quick Action Checklist

• Hard doesn't raise enemy health. It cuts your weapon damage to 75%, raises damage taken to 150% (200% in the Episodes), and shrinks ammo boxes to 60%.
• Lean on the gravity gun on Hard: physics impact damage skips the difficulty penalty entirely.
• Fight the Antlion Guard with thrown objects on Hard. Your guns and grenades hit it for about 56% of their Normal value, and thrown objects keep 100%.
• Use headshots against soldiers on Hard. They double damage on every setting.
• Don't count on the shotgun one-blast kill on Hard. Seven pellets do 42 against a 50-health soldier; use the double-barrel.
• Expect grenades when a Combine squad falls back on Hard.
• Budget seven rockets per Strider on Normal and Hard alike, and seven explosive hits per gunship on Hard.
• Falls, drowning, crushing, poison and sniper rounds hurt the same on every setting.
• Change difficulty any time from Options or with skill 1, skill 2 or skill 3. It applies instantly and no achievement checks it.