DOOM CAPTCHA

Original Article ↗ Hacker News Discussion ↗

A web experiment turns the classic game Doom into a CAPTCHA, requiring users to kill a few monsters to prove they’re human. Commenters praise the technical execution, nostalgia and clever satire of how hostile modern CAPTCHA systems have become, but many note that the challenge is surprisingly difficult, especially without modern controls, on mobile, or for people with disabilities. Others question its real-world viability, pointing out that Doom is deterministic and likely solvable by bots or scripted inputs, making this more of a playful proof of concept than a robust security measure.

Overall Reception

  • Many find the DOOM CAPTCHA hilarious, nostalgic, and technically impressive; it “hits just right” as both demo and satire.
  • Others find it excessively difficult and unusable, calling it “anti-human” or joking that failure proves they are bots.
  • Several say it’s still preferable to conventional image-based CAPTCHAs; others insist they would abandon any real site that used something this hard.

Gameplay, Difficulty & Strategies

  • The level is identified as E1M9 on Nightmare with a pistol start, which is notoriously hard even in the original game.
  • Lack of obvious strafing and non‑modern controls (arrow keys instead of WASD, no mouselook) dramatically increase difficulty.
  • Reported winning tactics:
    • Don’t move or just step forward then immediately back and hold fire.
    • Back into the starting doorway and snipe enemies at range.
    • Hug walls and pull enemies into a firing lane.
  • Many players cannot pass without cheating; others beat it in 1–3 tries and argue it’s manageable once you understand old-school Doom.

Controls, Mobile & Accessibility

  • No WASD or mouse fire; default is arrows + space, with strafing via Alt, comma/period, or < > depending on setup.
  • Platform issues: some browsers intercept Alt+arrow; some keyboards lack arrows or use non‑QWERTY/custom layouts.
  • Mobile has an on-screen pad, but multiple reports say it doesn’t appear or doesn’t register kills; lack of strafing on touch makes it “a shooting gallery.”
  • Many point out this is highly inaccessible for people with disabilities and non-standard input setups.

Cheats, Determinism & Security

  • Classic cheat codes work (IDDQD, IDKFA, IDSPISPOPD, IDCLEV, IDCLIP), though some weapons and kill types don’t count (e.g., rocket gibs, infighting, shareware‑only arsenal).
  • Users show trivial bypasses (e.g., calling Module.onEnemyKilled() in the console), noting this is only a proof-of-concept.
  • Discussion suggests more secure variants: randomizing spawns, recording inputs/demos and replaying server-side, using Doom’s determinism as a verifiable proof of work.

AI Tools & Captcha Philosophy

  • The page layout was largely created using Vercel’s v0 assistant; commenters note the chat log is mostly UI tweaking, with DOOM integration coded separately.
  • Some see this as a fun UX mockup rather than a serious CAPTCHA; others debate future viability as bots, RL agents, and agents-as-a-service become common.
  • Broader captcha discourse emerges: frustration with reCAPTCHA/hCaptcha, concern about accessibility, and skepticism toward Apple’s device-based “automatic verification” on privacy grounds.