<i>&gt; Once things moved on to Quake a lot of my friends lost interest in trying to &quot;figure it out&quot; as the editor was more challenging.</i><p>Moving to constructive solid geometry (CSG) map editing was really hard for a lot of people, myself included. I ended up learning on <i>Dark Forces 2: Jedi Knight</i>, which was subtractive and a lot more like how Doom felt to me.