Final 'Doom II' Secret Discovered After 24 Years, Ending The Agony For Completionists The final 'Doom II' secret has been discovered, so completionists will now be able to attain 100 percent in the iconic first-person shooter. The secret took 24 years to be found, prompting a congratulatory message from 'Doom' co-creator John Romero. by Aaron Mamiit