Great job capturing the spirit of refueling base, right down to the 'stumbling into trouble' encounter design. The overall feel was very otherworldly. As far as feedback goes:
+ The yellow key just seemingly discarded in the warehouse was perfect, as was the switch in the slime nearby
+ The library room was a brilliant layout, and the trap it leads to was one of the highlights of the level, a nasty trick on par with the warping cyberdemon in the original.
+ The auto-move triangle is a really distinctive feature that helps anchor an otherwise chaotic level. That said, I do think there should be a quick-lift to get back the way you initially come from. If you miss a jump while the lift is rising, you're basically dead since it takes so long to come back down.
+ I really like the openness of the level, it really gives the adventurous feel that made Sandy maps so fun. You might consider making some of the slime vat platforms move up and down like the triangle to make it a level theme - mixing the slime in some abstract sense.
- Ammo can be tight depending on the routes you take through the level, and I'd suggest more on certain paths , or perhaps a change in placement of the items. I'll make a lot of suggestions on it below, but to first boil down the problem: *following any one path to completion tends to leave you strapped for ammo*. A few that stand out in my mind:
- I don't feel like the 4 mancubi in the Nortwest corner really do the encounter justice - if you come from the right, they jam in the stairs and don't really do anything but waste your time, and if you come from the key warp you'll probably be hurt, so the best thing is to run past them and go up the stairs, with the same result. With plenty of them in the level already, I think these could be replaced by hell knights for better effect - you might even think you can handle them when hurt, and round the corner into the demon box or the hitscanners! You could keep one manc, the one closes to the red key stairs, and replace the rest for a threat that you can turn to an infighting opportunity.