Obsolete [Spawnflags] it's confusing for mappers and hacky to implement - you should use a property of an enum with [Flags] on it Removed Spawnflags from BaseTrigger, the only flags that did anything were Clients|Everything - everything should just work with tags instead. FuncPhysbox spawnflags turned into a flags enum property instead (old maps will still work just fine) Get rid of FGDType( "flags" ) usages, we just derive this automatically now from [System.Flags]