This is a map focused on creating challenging Marathon combat. What sets it apart is a water-themed aesthetic and battles that will require you to think outside the box to win. What I mean by that is that in Bungie's campaigns 95% of the time you could just charge in, blasting away with your MA-75 and that would solve any combat problem. But your usual combat tactics will not work in Almost Transparent Blue!

You'll be fighting a lot of enemies, often in close quarters or in situations where enemy ranged units have the high ground. Ammo is limited and there are no health rechargers. There are health canisters, but they should be used sparingly for obvious reasons. There are also plenty of save terminals, so if you beat one battle you'll usually have the opportunity to save so you won't have to beat it again. I normally play on Total Carnage, but I had to bring the difficulty level down to Normal for this map!

This is one of the very few Marathon scenarios where the TOZT is actually very useful. There's lots of close combat against organic enemies, giving the TOZT a chance to shine. And limited ammo for everything else means you've got a strong incentive to use the TOZT as much as possible.

One nice thing about the combat is that the enemies often start out passive, meaning they will not attack until you start shooting. This allows you to plan out your attack, and you'll definitely need to make plans, because as stated earlier the normal tactic of just blasting away with no plan will get you killed immediately on this map.

The water-themed architecture looks really nice, though I did feel it was a bit too dark in places. There's also some clever use of water pillars; basically you can use these pillars like stairs to gain elevation, and get to areas of the map that are otherwise inaccessible. I believe cassis did something similar in his Durandal Done Different level! My one concern about this is that the player is using oxygen during these underwater jaunts, but there are no oxygen rechargers anywhere on the map that I could find. This could result in the player getting softlocked if they spent too much time exploring underwater, and this could be a particularly big problem in the final fight, which requires the player to hide underwater for an extended period of time in order to survive.

Finding the final exit was the thing that took me the most amount of time on this map. I was trapped in a small room, but didn't realize there was a teleporter hidden under the water. I found it just as I was about to run out of oxygen!

There's some catchy music to go with this level that suits the aesthetics nicely. There is no storyline; everything is focused on combat. There did appear to be some secrets. At least, when I was able to get to some obscure corners of the map I found a magnum ammo clip, even though there was no magnum gun handed out at any time. I assume the magnum clips are like a reward for getting to a hard-to-reach area.

If you're looking for challenging combat then you should check out Almost Transparent Blue!