Any rookie can spray a Glock across the room, but the players who own the leaderboard on maps like snark_pit, crossfire and stalkyard win with their brains, not their trigger fingers. Gordon Freeman packs more than a crowbar -- he packs an arsenal of traps. Here is how the Zone's sharpest deathmatch veterans put explosives and living ammo to work.

Snarks: chaos on legs. A fistful of Snarks is the finest distraction in the game. Toss them into a crowded spawn or down a tight corridor and let the little critters hunt while you reposition. Use them for area denial around a health charger or the RPG pickup -- nobody wants to grab loot with three Snarks chewing on their ankles. A classic mind-game: lob Snarks around a blind corner, then wait a beat. The panicked footsteps tell you exactly where your target ran.

Tripmines: own the chokepoint. The laser tripmine is the patient killer. Stick one just past a doorway or at eye level around a corner where a sprinting player will never see it in time. On stalkyard, the crane ladders and narrow scrapyard gaps are perfect. Best of all, stack a mine low AND high on the same choke -- crouch will not save them. Salt the route to a power weapon and let the map do your killing.

Satchel charges: the ambush. Drop a satchel, walk away, and hold the detonator. Plant one under the RPG or the .357 pickup, back off to a safe spot, and wait for a greedy soul to stroll in. On crossfire, the tactical nuke silo is bait city -- rig the approach and thumb the trigger the instant they commit. Chuck satchels down from a ledge onto a group, then blow them mid-cluster.

Laser-guided RPG: patience pays. The RPG's laser lets you steer the rocket, so you do not need a straight shot. Fire down a hallway and curve the missile around the bend into a camper's face. Just remember -- that bright red dot warns sharp opponents, so paint late and commit fast, or lead with a dumb-fire snap shot up close.

Keep these habits and the pit is yours:

• Never walk your own choke -- you set those mines, so route around them.
• Reload the RPG in cover; that steering laser is useless while you are fumbling a rocket.
• Listen. Snark shrieks and a distant tripmine beep are free intel on where the enemy is.

Golden rule: everyone on the Zone must run the same Half-Life version, so grab the latest WON patch from the Downloads page before you host. Mismatched builds mean your traps will not spring the same for everybody. Now go set the perfect ambush. See you in the pit!