Wow - the WAD editors have come a long way since 1995 - and I guess that with contemporary computing power, one doesn&#x27;t have to wait a few minutes while the level renders, only to find a stupid bug to fix and render again... Which reminds me about all the quirks of Doom&#x27;s 2.5D mode that the article doesn&#x27;t get into - for example, put a texture on the wrong side of a wall an you&#x27;ll get ugly artefacts... Lots of those gotchas to watch for... Oh the nostalgia... Doom levels have been my biggest foray in game content creation - I did the 2.5D modeling and three business school friends handled sound, music and texturing... Borrowing school hardware and organizing a 250-people tournament of two-people teams (Doom&#x27;s IPX multiplayer allowed only four players) was a highlight of those times !