Half-Life: Source: Complete Guide

A guide to Valve's 2004 Source-engine port of Half-Life: what's different from the original, a chapter-by-chapter walkthrough outline, weapons, boss strategies, and the bugs and settings worth knowing about on a modern PC.

Researched September 2026 — current as of the last Half-Life: Source update (November 4, 2013). Live games change; check the linked sources if something differs.

Should you play this version? Half-Life: Source is a direct port of the 1998 game to the Source engine — same levels and models, new physics, water and lighting. Fans generally rate it below the original: Combine OverWiki notes poor reception and bugs worsened by the 2013 SteamPipe update, and Wikipedia notes retrospective criticism for instability. Combine OverWiki also reports that Valve delisted it on November 17, 2023 (the series' 25th anniversary) in favor of the original; however, Steam's store data still returned a purchasable package when checked in September 2026, so availability may vary. If you own both, the updated original Half-Life is the recommended way to play; if you want a full remake, look at the fan-made Black Mesa (released 2020). This guide covers Source specifically, but the walkthrough applies to both.

Quick Start

• Quicksave constantly. The default quicksave key is F6 and quickload is F9. Half-Life has no checkpoints you can rely on.
• Crouch-jump to reach ledges. Jump then crouch mid-air to clear higher obstacles. It's needed for many platforming sections.
• Charge up at wall stations. HEV chargers restore suit armor; health stations restore health. Top up before every big fight.
• The HEV suit is essential. Without it (the very start) you can't pick up weapons. The suit also absorbs damage.
• Watch for the long jump module. Later you get a long jump: hold crouch and press jump while moving forward.
• Physics objects are new in Source. Crates and debris behave with ragdoll-era physics — occasionally helpful, occasionally buggy.
• Try the HD pack only if you like it. Since 2013 an optional HD pack can be toggled in Options → Video; it swaps in the higher-detail models from the old "High Definition" add-on.
• Don't rush Xen. The low-gravity jumping is imprecise; save before every jump.

What's Different from the Original

Change | Detail

Physics | NPCs become ragdolls on death and cannot be gibbed; many objects use Source physics

Water and lighting | Reflective water, improved lighting, higher texture quality

Skies | 3D skyboxes replace flat bitmap skies

Sound | Many interaction sounds (buttons, doors, breakables) reuse Half-Life 2 audio; 5.1 surround support

Level tweaks | The canyon in Surface Tension was changed

Player death | The camera no longer tilts sideways; your weapon visibly drops

Models/animations | Mostly unchanged — which is the main criticism

2013 fixes

Valve's September–November 2013 updates moved the game to SteamPipe, added Mac and Linux support, added the optional HD pack, fixed a crash during the Apache helicopter fight, restored drowning sounds, set the Glock to 17 rounds per magazine to match the original, and fixed the missing HEV suit when starting at "Unforeseen Consequences" and "Residue Processing" via chapter select. Several of the Source port's quirks remain.

Controls

Action | Default

Move | W/A/S/D

Jump | Space

Crouch | Ctrl

Use (buttons, chargers, scientists/guards) | E

Flashlight | F

Reload | R

Quicksave / Quickload | F6 / F9

Long jump | Crouch + Jump while moving (after getting the module)

Scientists and security guards follow you when you "use" them — guards fight alongside you and scientists open retinal-scanner doors.

Chapter Walkthrough Outline

Half-Life has 19 chapters.

# | Chapter | What to expect | Tips

1 | Black Mesa Inbound | Tram ride intro | Just enjoy it

2 | Anomalous Materials | Suit up, the resonance cascade | Grab the HEV suit before leaving the locker area

3 | Unforeseen Consequences | First headcrabs and zombies; crowbar | Use the crowbar on headcrabs to save ammo

4 | Office Complex | Offices, first firearms, security guards | Recruit guards; watch for ceiling barnacles

5 | "We've Got Hostiles" | The Marines (HECU) arrive | Take cover; grenades hurt; they flank

6 | Blast Pit | The tentacle creature in the silo | Stay quiet — it hunts by sound; restore power, oxygen and fuel, then fire the rocket engine

7 | Power Up | Restore power to the rail system; a Gargantua | You can't kill it with normal weapons; lure it into the electrified generator

8 | On a Rail | Drive the rail cart; launch a rocket | Watch the tracks and switches

9 | Apprehension | Water-filled facilities; ends with Freeman captured | Watch the water; save before the ending sequence

10 | Residue Processing | Dumped in a trash compactor and starting without weapons; conveyor belts and hazards | Careful platforming; quicksave often

11 | Questionable Ethics | Labs and more alien weapons | Use scientists to open doors

12 | Surface Tension | Outdoors: Marines, tanks, an Apache helicopter and another Gargantua | Call in the airstrike on the Gargantua; RPG the helicopter

13 | "Forget About Freeman!" | Marines everywhere, underground | Laser trip mines and satchels are great here

14 | Lambda Core | Reactor cooling and teleporter puzzles | Map the teleporters mentally; save before each jump

15 | Xen | Low-gravity alien world | Long jump carefully; save before each leap

16 | Gonarch's Lair | The Gonarch boss | Keep moving, use explosives and heavy weapons

17 | Interloper | Alien factory | Vortigaunts and alien grunts; conserve Gluon ammo

18 | Nihilanth | Final boss | See boss tips below

19 | Endgame | Ending sequence | Your choice decides the ending

Weapons

Weapon | Use

Crowbar | Headcrabs, crates, saving ammo

9mm pistol (Glock) | Early all-rounder; 17-round magazine since the 2013 update

.357 Magnum | High-damage precision

Submachine gun (MP5) | Main automatic weapon; has a grenade launcher

Shotgun | Close range; secondary fire shoots both barrels

Crossbow | Scoped; silent and strong, fires underwater

RPG | Laser-guided rockets for tanks and helicopters

Tau Cannon | Can charge shots; charged shots pierce walls and can propel you

Gluon Gun | Beam weapon; shreds almost anything, eats ammo fast

Hivehand | Alien bio-weapon with regenerating ammo

Hand grenades | Rooms and groups

Satchel charges | Remote-detonated explosives

Laser trip mines | Traps for Marines

Snarks | Throwable alien creatures that attack whatever's nearest

Enemies

Enemy | Tips

Headcrabs / zombies | Crowbar; zombies are slow, back-pedal while swinging

Barnacles | Ceiling tongues that pull you up; shoot them or crowbar them when lifted

Houndeyes | Sonic blast; kill before they gather

Bullsquids | Spit acid; strafe

Vortigaunts | Electric attacks with a visible charge-up; interrupt with gunfire

Alien grunts | Tough; use the shotgun or explosives

HECU Marines | Smart flankers with grenades; fight from cover

Black Ops assassins | Fast and acrobatic; watch corners

Gargantua | Don't fight it head-on; use environmental kills

Boss Tips

• The tentacle (Blast Pit): it reacts to sound. Walk, don't run, and throw grenades to distract it. The solution is to restore oxygen, fuel and power, then fire up the rocket engine test.
• Gargantua (Power Up): lead it into the generator's electrified area once it's powered.
• Surface Tension Gargantua: call in the airstrike to deal with it.
• Gonarch: keep moving, stay away from its baby headcrabs, and hit it with RPG, Tau or Gluon damage when it exposes itself.
• Nihilanth: destroy the golden energy orbs that protect it, dodge its teleport attacks, and then shoot its exposed head. Destroy the healing crystals around the arena so it can't recover, and use the arena's platforms to get level with its head.

Common Mistakes to Avoid

• Not saving before jumps and big fights. Xen and Residue Processing will make you regret it.
• Playing through the Marine sections without cover. They flank and throw grenades.
• Spending Gluon ammo early. It's your trump card for the last chapters.
• Fighting the Gargantua directly. Use the level's solutions.
• Assuming Source is the definitive version. It's a port; the updated original and Black Mesa are often preferred.

Advanced Tips

• Tau Cannon jumping: charging the Tau and firing at your feet propels you — a classic speedrun trick.
• Crowbar everything cheap: headcrabs and barnacles are free kills that save ammo.
• Use Snarks on groups and walk away.
• Scientist escort: stay close so they don't get lost; they open retinal scanners.
• Chapter select: jump to any chapter you've reached via New Game.
• HD pack: if animations look off, toggle it back off in Video options.

FAQ

Is Half-Life: Source worth it over the original? Most players prefer the updated original Half-Life or the Black Mesa remake. Source adds physics and water but keeps the same models and introduces bugs.

Does Half-Life: Source have achievements? No.

Is it still for sale? Combine OverWiki reports Valve delisted it in November 2023, but Steam's store data still showed a purchasable package in September 2026. Check the store page in your region.

How do I fix the missing HEV suit when starting a chapter? That was patched in November 2013 for "Unforeseen Consequences" and "Residue Processing". Make sure your install is up to date.

How long is Half-Life? Around a dozen hours for a first playthrough, depending on how often you die in Xen.

Does it run on Mac and Linux? Yes — native Mac and Linux support was added in 2013.

Sources

• Half-Life: Source — Combine OverWiki
• Half-Life — Combine OverWiki
• Half-Life (video game) — Wikipedia
• Half-Life: Source news and update notes — Steam
• Half-Life: Source — Steam store page