Big Fish Boss

"Ah, my Fish Legions! Show no mercy! Kill the planet! Kill the planet! KILL THE PLANET! The Galaxy is for Fish!"

- Big Fish Boss ordering the destruction of a planet

Big Fish Boss is the ultimate main antagonist of the entire Ratboy Genius Universe. He is an unrelenting dictator who wishes to become powerful enough to become the leader of the Galaxy - using the threat of absolute destruction.

Personality
While all other Ratboy Genius characters have proven to be sympathetic -- even the villains, with misguided motives and a way of redemption -- the Big Fish Boss is a merciless and terrible warlord who only has one goal in mind: Complete control of the Galaxy.

He has absolutely no remorse for anyone else, and is perfectly willing to suck the energy out of stars (hereby killing entire solar systems) to further his own needs. To top that off, he also destroys random planets as a display of power.

He is a great speaker, as shown when he successfully manipulated the entire species of the noble Fish into becoming his mindless soldiers.

Origins
Not much is known about Big Fish Boss' past, but according to Ratboy Genius,  there have been multiple Fish Bosses. Ages ago, another Fish Boss attacked Mars, killing all life on the planet and creating what is now known as Valles Marineris.

In Ratboy Genius Dreams Minecraft
Big Fish Boss is implicitly the unseen Bigger Bad of the series, since his reign of terror is what caused the creation of the Minecraft dimension, which Ratboy Genius explores without yet knowing he created it.

In Galactic Superheroes
Big Fish Boss serves as the main antagonist of Galactic Superheroes 03''. ''In the third and currently final episode, a pack of fish is attacked by a singing Fisheater, and most of them are devoured. The few who manage to escape quickly tell Big Fish Boss about the attack, and he becomes furious, saying they need every fish to complete his master plan.

Shortly after, he orders his Fish Legions to brutally tear Fisheater apart, chanting during the violent process. After Fisheater has been dealt with, Big Fish Boss exclaims that the Galaxy is for fish, and then flies off.

In Starship Genius
Big Fish Boss makes a surprise appearance in STARSHIP GENIUS 2 - Trouble's Coming and reclaims his position as the main antagonist of the Ratboy Genius universe.

In the episode, just after Fred tells Ratboy Genius to watch out for the Fish, Big Fish Boss emerges and orders his Fish Legions to "kill" a lonely planet (i.e. destroy it). He repeatedly screams his orders as the planet is totally annihilated, and like always, he shares his philosophy that the Galaxy is for fish before leaving.

In the third episode, The Professor explains that the Big Fish Boss is using his Legions to weave cosmic webs between the stars, charging up fatal electricity capable of destroying planets with ease. With the threat of chaos, he'll be able to control the Galaxy.

Big Fish Boss makes no appearance in episode 4, but his main form of attack, the Cosmic Thunderbolt, is revealed. While Big Fish Boss does not appear in episode 5 either, Ratboy Genius gives Summer Solstice Baby an explanation as to why the Fish are blindly dooming themselves under Big Fish Boss' command. He manipulates them, and they "forget that they are noble and free". Big Fish Boss makes a cameo appearance in episode 7, now in his new 3D model appearance.

Big Fish Boss makes an appearance towards the end of episode 10 at the fish rally. He exclaims how his master plan is almost ready.

Quotes
"No! This must not happen! We cannot lose Fish! We need every Fish to complete my master plan!"

- Big Fish Boss' first appearance and line, revealing him as a much bigger threat than the Fish Eater

"Let's go! Get the Fish Eater! Tear him to pieces!"

- Big Fish Boss chanting as he has his Legions violently mutilate Fish Eater alive

"Ahh! My Fish Legions! Our time is nigh! Our power is high! The galaxy can hear our cry! We are now ready to complete my master plan! THE GALAXY IS FOR FISH!"

- Big Fish Boss' ominous speech

Trivia

 * While all other Ratboy Genius villains are sympathetic, arguably tragic figures that at some points agree to help the protagonists, Big Fish Boss is absolute Pure Evil, as he manipulates an entire species, causing them to forget they are free creatures and driving them to suicide in warfare, has his henchmen tear whoever he dislikes to pieces as he eggs them on and orders the destruction of countless innocent planets just to further his own goals.
 * Furthermore, the Big Fish Boss is not even aware of the heroes' existence, cementing him as an unstoppable force of horror.