Black Mesa Achievements Here is the full list of all 50 Black Mesa achievements. It takes around 20-25 hours to unlock all of the achievements on Windows.Filter Achievement View View Image viewList view Sort by TrueSteamAchievement desc TrueSteamAchievement asc Achievement name desc Achievement name asc TSA Ratio desc TSA Ratio asc Gamers desc Gamers asc Steam order Date won desc Date won asc What are achievement flags? Click to find outApply Brownian MotionPass the toilet paper to the scientist in need. 1 guideCaffeine ExtractionPerform surgical caffeine extraction from 20 machines. 1 guideCalculated TrajectoryKill 10 Airborne Headcrabs using the Shotgun. Centripetal AttractionKill 20 enemies with the Hivehand. Convection RefinementRuin the microwave casserole. 1 guideDead ReckoningKill an Assassin with the .357 Magnum. Digital WizardryKill 10 enemies with a reprogrammed Sentry. Ethically QuestionableConduct all of the questionable research experiments. 1 guideFutile ResistanceKill 10 enemies with Snarks. 1 guideGray Matter PropulsionHeadshot 20 enemies with the .357 magnum. Hyper Saturation ConundrumDrown in Lambda Core's coolant. 1 guideInflammatory ActionsKill a Headcrab using fire. 1 guideKinetic RepulsionKill a Marine with their own grenade. Mega HertzKill 5 enemies with one grenade. Nuclear Fishin'Kill an Icthyosaur with either the Tau or Gluon. Permeable InfrastructureUse the alternate path in Office Complex. 1 guidePremature ExpulsionUse an entire clip of Gluon ammo in one continuous shot. Prophylactic SuggestedGet overtaken by a Headcrab's ample anterior. 1 guideProverbial TinkererInterfere with the alarm and laptop in Anomalous Materials. 1 guideQuantum CapacitanceOvercharge it anyway. Rare SpecimenSend the Hidden Hat to Xen. 1 guideRemote DetonationKill a Barnacle with a Satchel. 1 guideResonance ProcrastinatorRefuse to insert the specimen into the Anti-Mass Spectrometer. 1 guideUnified Coupling TheorumHelp the Barnacle and Headcrab find true love. 1 guideUniversal GravitationGet killed by your own Snarks. Prolific PopperKill all Protozoans in the Borderworld. PhD in PacifismDon't kill any Vortigaunts in the Borderworld. 1 guideThe Rarest SpecimenCarry the Hidden Hat to Endgame. 1 guideOne Step AheadKill 10 Enemies with Tripmines. Stealth TechnologyEscape the Hangar in Surface Tension without alerting the Soldiers. xen whenWait too long to jump into the Lambda Teleporter. 1 guideOur Brains And Your BrawnAssemble all the possible Scientists and Guards at the end of Office Complex. Less Than Desirable ConsequencesDie in the AMS Beam before starting the experiment. 1 guideOrbital TrajectorySkip the opening Xen island with a secret jump. 1 guideFollowing the RulesUse the welcome mat. 1 guideDoctor’s SignatureDeliver the finishing blow to Gonarch with your Crowbar. Gonad GliderGet whacked into oblivion in the ledge fight. 1 guidePost-Mortem IntervalFind each member of the missing research teams. The PlanUse Cyanogen to kill Gonarch. 1 guideUnquestionably EthicalDon't use the Cyanogen and let the Gonarch live. 1 guideContest PropellantFind the snack supply canister. 1 guideLaser ImmunizationComplete Interloper without taking any laser damage. 1 guideBlack Mesa Decathlon WinnerEscape the Gargantua’s Lair without taking any damage from Gargantuas. 1 guideAnti-Matter Over MindKill a Controller without killing any of its mind-controlled Vortigaunt slaves. 1 guideSpecimen GGTake out all three Healing Crystals in Nihilanth’s Chamber at the same time. 1 guideLate for WorkDefeat Nihilanth in under 4 minutes. 1 guideLimitless PotentialAccept G-Man’s offer of employment. 1 guideRather an AnticlimaxDecline G-Man’s offer of employment. 1 guidePepperoni PrecipitationView the *other* secret ending. 1 guideWell-DoneCook a Grenade for too long. 1 guide