Let me set the stage, for those not in the know. On the level The Ark, after clearing out the two AA Wraiths, the FUD comes down and provides you with tanks. In speedrunning, we just take the ghosts we used to get there, but legendary has always eluded this. Only when segmenting and through intense repetition could we complete this trip without the tank on such a difficulty, and if it could be done reliably, it saves anywhere from 30 seconds to over a minute versus the tank. I recommend reading the description for some more information. I and others have done a lot of work with this, and I won't be able to credit everyone, but I'll credit those that helped me whether they knew it or not.