Since this got somewhy somehow somewhat popular I'll post here what it is and how to host it.
How:
1) !map icy run v2 (or something narrow and wide)
2) !setoptions zkmode=halloween,ghostdiff=nightmare,ghostgraceperiod=9999
What:
Detriment will spawn near the middle of the map and haunt other players. This is not complete halloween, no ghosts will haunt players and take their stuff.
So the objectives becomes:
1) Get fastest radar coverage possible, spam small radar at any hill.
2) a) If detriment walks to your base. Fall back and wait. Build E structures in corners if possible, land down all planes, selfd anything that can be seen by it.
b) If detriment goes away, advance and build wall accross entire map, that is higher than 200 in height so that detriment won't see your team at all, anything more than 30-40 stops him from walking in, yet he will see and kill.
3) Eco as fast as possible and defend yourself and team from any sneak tactics as well as be wary of enemy trying to terraform your wall down with sneaky cons, fleas or quake missiles when detriment is near.
4) Out-eco and nuke, or maybe 4 emp missiles at det and pick him with vindicator, or just successfully perform sneaky operation and kill all enemy singularities. Make your choice.
Some folk may provide screenshots of typical matches, if they bother to watch some replays. Because I for one, right now am too lazy. xD