Half-Life 2: Update

Airboat Navigation: Use the airboat to traverse the toxic hazardous waste canals. Jump ramps by releasing the throttle slightly before takeoff.

Hunter-Chopper Boss Battle: Once the mounted pulse cannon is attached at the rebel outpost, circle-strafe the Hunter-Chopper and shoot down its dropped aerial mines before they detonate.

Gravity Gun Training: Practice throwing and catching objects with Alyx and D.o.g. at the scrapyard.

Ravenholm Survival: Conserve standard ammunition by using the Gravity Gun to launch circular sawblades, propane tanks, and engine blocks. Team up with Father Grigori at the cemetery to reach the mine cart elevator.

Buggy Traversal: Drive the scout buggy along the coastal highway. Use the wire-guided RPG to take down Combine Gunships by keeping your laser sight steady on the fuselage.

Antlion Guard & Pheropods: Defeat the Antlion Guard at the beach perimeter to obtain Pheropods (Bugbait), allowing you to summon and command swarms of Antlions to breach Nova Prospekt.

Turret Defense: Set up 3 automated Combine turrets in triangular formation to defend the teleporter room while Alyx initiates the extraction.

Supercharged Gravity Gun: Inside the Citadel confiscation beam, the Gravity Gun absorbs dark energy, allowing Gordon to vaporize Combine Elites, rip heavy console terminals, and deflect energy orbs directly into the dark fusion reactor.

• Singing Vortigaunt Cave: In Water Hazard, near the drain pipe gate, climb the steel beams to find a hidden cave where a singing Vortigaunt roasts a headcrab and reveals cosmic prophecies.
• Keep Off the Sand!: Cross the entire beach in Sandtraps using wooden pallets and rocks with the Gravity Gun without stepping on sand once to unlock this prestigious achievement.
• All 45 Lambda Caches: Look for yellow Lambda (λ) graffiti spray-painted on walls throughout City 17, indicating concealed ammo crates and health dispensers behind wooden planks.