I am with a group of others I don’t remember on a huge pool of water. It is a man-made ocean, unfathomably deep but only about a mile in diameter. I know that somehow the waves and depth of the water is controllable, but I am not the one in control of it. Me and the others stand on a platform above the water and fight large sea creatures that appear. One looks like a sperm whale with thick gray elephant-like skin and extra fins that are jagged and torn, and another is a plesiosaur that erratically twists it's body and head around as it fights us. Fighting them has a similar feel for me to the swimming and water-based fights in a Monster Hunter game: daunting and slight irrational panic-inducing (due to deep water fear), but no real sense of danger. As usual in swimming-related dreams, I am terrified of touching the water, even just a toe dipped in will get me eaten, but the platform I'm on keeps getting knocked around and I end up falling in several times. Each time, I panic and suddenly, I appear back onto the platform. I don’t realize I'm dreaming, but the feeling of lucid control is there. The others and I fight the giant sea creatures with random weapons like spears and swords-- slashing at the monsters and managing to land heavy blows despite the range of the weapons-- and also using the platform to bash into them. I don’t do anything but think about the platform bashing them in order for it to happen and it feels like I am using the help of the others to do it.
After chaotic battling and falling into the water a bunch of times, an even bigger monstrosity appears. All I can see from above the surface is a massive dark shape in the water. The silhouette looks like a ship, the front side pointed and the back larger and blocky. This ‘creature’ makes the other monsters look tiny in comparison (even though I have not played any Monster Hunter game in years, I can see the sand-sea battle with Dah’ren Mohren from Monster Hunter 4 Ultimate influence here, though this dream-version is way bigger). My comrades and I are able to land heavy blows on it too and now I lucidly make myself unable to physically touch the water at all. When I am about to get knocked into the water, I lucidly go “nope!” and force myself to remain on the platform (quite useful in preventing my worst nightmares from happening!). At some point, we are able to land a blow on the huge monster that makes it fly out of the water, and I can see that it is actually a metal transport ship that had sunk and had supernaturally gained animalistic life somehow.
Then, I am knocked into the water again and sink like a rock below the surface. I quickly lucidly control the water and use it to push myself back to the surface. My desperation to get out of the water causes me to make the entire sea level rise super quickly and I fly with the sea underneath me up into the sky. There are floating cliffs and platforms that I can see, but I wake up before anything else happens.
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Many of my dreams have a fear-of-water theme to them and obviously my subconscious thinks it’s a big deal, but in reality I am mostly capable of rationally taking care of it and generally don't panic when swimming. I play a lot of videogames and avoid deep water usually, but any missions that involve swimming down into the middle of the lake or a sunken pirate ship, I will do it, and I will fight those massive terrifying sea-beasties in Monster Hunter-- though panic does screw me up frequently. I understand the fear-of-deep-water is just a fear-of-the-unknown about what deathly things might be lurking just out of sight down there, but understanding the fear hasn’t exactly ‘cured’ the fear. I at least have figured out how to defend myself from it in dreams for the most part.