- Awesome Music: Practically the entire game is filled with it. Perhaps the best being Fear the Dark, sung by the protagonist herself, and reflecting on her journey.
- Breather Level:
- Compared to earlier areas of the game, The Veil is absurdly spacious and almost completely lacking in dangerous creatures. Also a literal Breather Level, since you take your first breath of air above the Veil.
- To say nothing of the Ice Cave and Frozen Veil, which do not contain a single enemy between the two of them which actively attacks you (and many enemies there can't even do collision damage). They do lead up to a tricky Bonus Boss, though actually reaching it involves difficult moves.
- Cry for the Devil: You've spent the entire game witnessing the effects of the Creator's mad fury, and putting the remains of his creations out of their misery. And then, once you've defeated him, you find out he was a little boy whose entire family was killed, and "I should have died with them". He's spent hundreds of years trying to create someone who would love him like his mother did, and failing.
- Demonic Spiders: Mutants (mutated Mithalans) in the Cathedral and clockwork crabs in the otherwise relatively sedate Sun Temple—the crabs far outstripping the mutants in terms of trope qualifications. Then there are the things you find in the Sunken City.... Averted by the spider-crabs you see in the Abyss: those are just mobile traffic hazards that run from light.
- Fridge Brilliance: The special ending threw a lot of people in for a loop for its completely juxtapositional and sad outcome in comparison the normal ending. However, if you listen to Naija's narration, this ending has been hinted throughout the entire game. Naija repeatedly mentions that something tragic happens at the end of this story, specifically to her. She also keeps mentioning wanting to never remember anything at all (critical here). At first, the viewer reads it as the downfall of Aquaria, but that doesn't really make much sense because she gets a happily ever after ending. On the other hand, the special ending, in which Mia reveals her manipulation of Naija and the memory wipe, fits the narration much more perfectly. Moreover, the special ending is triggered by finding the three lost memories, which are indicated by an icon of Mia's phantom form. This indicates that Naija is at least subconsciously aware of Mia's memory wipe, and explains why she never wanted to remember in the first place.
- Goddamned Bats: Moneyes, though they do have useful drops, being the primary source of two important ingredients for healing items.
- Nightmare Fuel: Now has its own page.
- Quicksand Box: It won't be a Metroidvania game without it, sadly. It can be quite confusing on where to go.
- That One Achievement:
- No Escape: You have to find and kill an enemy that you would normally never see on-screen; you have to use the 'look' function to find out where it is and blast it with non-homing shots while it's off-screen. Trying to figure out where this enemy is more a challenge than actually beating it.
- Weird Fish & Explorer: These two achievements go hand in hand; the two weird fish are hidden in a separate room through a fish tunnel that, unlike other fish tunnels, is all but unnoticeable. There are no hints to where the fish tunnel is in the mini-maps, unlike other hidden areas.
- Super Chef: Finding all of the recipes involves much Trial-and-Error Gameplay, since a good portion of them aren't given out by the game itself, or are dropped infrequently by rare enemies.
- Speed Racer: Finishing the Arnassi race in under a minute requires sharp turns, speed-boosting items, and an optional form or two, and even then, it's still extremely easy to get stuck during the circuit, when the time limit is extremely tight as it is.
- That One Boss:
- Octomun. Hope you stocked up on healing foods — you're juggling at least two forms, dodging energy balls and ink-squrting squid, keeping the lights on, and trying to hit a briefly-visible target without getting grabbed and pounded against the floor.
- The King Jellyfish. You have to switch back and forth between Beast Form (to eat the pink jellyfish enemies that are invulnerable to everything else) and Energy Form (to shoot at the eye through the small gap in the spastically-spinning shield that surrounds it.) All this while dodging massive spinning lightning bolts. Have fun.
- However, the final form makes it trivial, as there are plenty of floaties around to charge your scream attack, the attack itself clears the screen of enemies, and three screams will kill the beast.
- That One Level: The Frozen Veil and to a lesser extent The Veil as well, due to the fact that you have to go onto land at a few points. Unfortunately, you're a sea creature who can't actually walk, only leap around. The Frozen Veil also involves a lot of bubble jumping, some of which are extremely tiny. Exiting a bubble causes Naija to vault in that direction at very high speeds, making it hard to control, and if you fall, you have to start the whole sequence all over again. AGH. On the other hand, both are good places to collect various resources. Or just do a Beast Form jump onto the crystal below the entrance to the area you normally reach by bubble jumping and skip the whole thing.
YMMV / Aquaria