SlipStreamer (or SlipStreams_65) of the now defunct Titans UT community was the mastermind behind this goosechase, that's who

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Anyway, I was considering posting the same lengthy writeup, but was kinda bored to slog through it, so now that the Worm has taken care of that, I can just settle for offering more bite-sized, practical tips to anyone hoping to get the hang of this in offline play. Which is basically code for cheats!
- These commands aren't enabled during online play (for reasons that will become all too obvious), but when you're the master of your own offline game, you can use the different rendering console commands to your advantage. Specifically, since you're looking for unnoticeable areas in both pools, you can pull down the console and type
rmode 1 to switch to wireframe view and quickly locate where the hidden (western) control room and the (eastern) vertical tunnel are. Since rmode isn't a toggleable command (its syntax is "rmode X" where X goes from 1 to 15 I think), to return to normal, dynamically lit rendering mode you'll need to type
rmode 5; also of use for finding stuff hidden in absolute darkness is the "textured", i.e. everything fully lit, view which you get with
rmode 6. The most convenient way to access those is by keybinding 'em to 3 adjacent keys for all kinds of map testing purposes; for me that's the comma, period and slash keys for wireframe, normal and unshadowed mode respectively. That takes care of the underwater locating part.
- When navigating the kill volumes maze, there's one other console command you can use to understand exactly how the volumes have been placed: the toggleable
show volumes command.
As mentioned before, those won't work online, so make sure you memorize the whole thing as best as you can. What's probably far worse for the ultimate goal of anyone trying all this, however, is that these 2 invisible movers Wormbo mentioned that rotate at the top of the central area have repeatedly been reported to be moving pretty erratically in online games (likely caused by the server's chosen tickrate) to an extent where it becomes pointless to go through the whole ordeal just so you can plummet down below almost as soon as you can see the manta within reach in the distance. Much like all of you now, I tried getting that manta a number of times years ago on some servers, even during off hours when I'd be all alone, and the first mover would still manage to kick me off it even as I was just standing there. So, all in all, yeah, you're better off trying what Cheese_it proposed in the previous page, i.e. to shield jump your way on top of your enemy's core door adjacent arch and fire some shit at your manta (rockets, shock shots, etc.) till that sucker drops. At least that method's known to (eventually) work

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