Champion Lobster
Finish the story as the spiny lobster character. This is easiest to accomplish on the Easy difficulty, as you can play on any difficulty and get a grip of the character for this achievement.

Champion Corn Barnacle
Finish the story as the corn barnacle character. This is easiest to accomplish on the Easy difficulty, as you can play on any difficulty and get a grip of the character for this achievement.

Champion Snow Crab
Finish the story as the snow crab character. This is easiest to accomplish on the Easy difficulty, as you can play on any difficulty and get a grip of the character for this achievement.

Champion Frog Crab
Finish the story as the frog crab character. This is easiest to accomplish on the Easy difficulty, as you can play on any difficulty and get a grip of the character for this achievement.

Champion Squilla
Finish the story as the squilla character. This is easiest to accomplish on the Easy difficulty after you beat the game with another character, as you can play on any difficulty and get a grip of the character for this achievement.

Champion King Crab
Finish the story as the king crab character. This is easiest to accomplish on the Easy difficulty after you beat the game with squilla, as you can play on any difficulty and get a grip of the character for this achievement.

Champion Hermit Crab
Finish the story as the hermit crab character. This is easiest to accomplish on the Easy difficulty, as you can play on any difficulty and get a grip of the character for this achievement.

Champion Anomalocaris
Finish the story as the anomalocaris character. This is easiest to accomplish on the Easy difficulty after you beat the game with king crab, as you can play on any difficulty and get a grip of the character for this achievement.

Champion Diver
Finish the story as the diver character. This is easiest to accomplish on the Easy difficulty after you beat the game on EX, as you can play on any difficulty and get a grip of the character for this achievement.

Champion Ebizuka
Finish the story as the king crab character. This is easiest to accomplish on the Easy difficulty after you beat the game with diver, as you can play on any difficulty and get a grip of the character for this achievement.

Lengendary Lobster Finish the story as the spiny lobster character on Hard. I had great luck achieving this by abusing the level 1 melee skill. One issue to take in mind is that the longer the round goes, the more likely the game is to crash due to too many particles. Having an aggressive play-style while holding a high hit-point fish is key to beating the game.

Lengendary Corn Barnacle Finish the story as the corn barnacle character on Hard. I had great luck achieving this by abusing the level 1 melee skill whilst spamming more and more barnacles in a wide area. One issue to take in mind is that the longer the round goes, the more likely the game is to crash due to too many particles. Having an aggressive play-style with keeping up the barnacle numbers is key to winning with this character.

Lengendary Snow Crab Finish the story as the snow crab character on Hard. I have yet to get this achievement due to crashing too many times, but having an aggressive play-style while holding a high hit-point fish is key to beating the game.

Lengendary Frog Crab Finish the story as the frog crab character on Hard. I have yet to get this achievement due to crashing too many times, but having an aggressive play-style while holding a high hit-point fish is key to beating the game.

Lengendary Squilla Finish the story as the squilla character on Hard. I have yet to get this achievement due to crashing too many times, but having an aggressive play-style with melee skills while holding a high hit-point fish is key to beating the game.

Lengendary King Crab Finish the story as the king crab character on Hard. I have yet to get this achievement due to crashing too many times, but having an aggressive play-style with melee skills while holding a high hit-point fish is key to beating the game.

Lengendary Hermit Crab Finish the story as the hermit crab character on Hard. I have yet to get this achievement due to crashing too many times, but I have learned that the AI is programmed to run if you have your shell on. Dropping the shell and re-equipping it with the level 1 skill is a surefire technique to avoid dying while keeping that aggressive play-style with melee skills intact.

Lengendary Anomalocaris Finish the story as the anomalocaris character on Hard. I have yet to get this achievement due to crashing too many times, but having an aggressive play-style with melee skills while holding a high hit-point fish is key to beating the game.

Lengendary Diver Finish the story as the diver character on Hard. I have yet to get this achievement due to crashing too many times, but this character is squishy. Making sure to abuse the point that he is very mobile is key to winning.

Lengendary Ebizuka Finish the story as the Ebizuka character on Hard. I have yet to get this achievement due to crashing too many times, but this character is EXTREMELY squishy. Making sure to abuse the point that she is very mobile is key to winning.

Domination of Aquarium
Finish the EX. I completed this with Squilla, as the level 1 ability with stronger melee allowed me to kill the diver with ease. Keep in mind you can upgrade your aquarium to be able to get materials more efficiently!

Squilla, King Crab, Anomalocaris, Diver, and Ebizuka all need to be unlocked with special requirements. This guide below can help understand such requirements.
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