Hi, I'm Mariobilly, a new member of this wiki, and I wanted to share my ideas for the Cthulhu boss. I was originally gonna make this a comment on the Cthulhu page, but I knew it would be too long.
I think that it will be able to regenerate body parts since it was powerful enough to give them life, and managed to survive without the most vital organ in the body (except for jellyfish, some bugs, and micro-organisms). I also believe it will have the power of Corruption, Crimson, Hell (and possibly Hallow and Underground) combined, and takes you to another dimension (R'lyeh) for the battle that decides the fate of Terraria, and you must defeat all other bosses to challenge it, and after you have beaten all bosses, you will automatically be brought to R'lyeh, and he will summon other monsters to attack you, but the NPCs and animals will help you by providing weapons, combat, healing, and gear. Also, they should make a part after where a rouge scientist uses the remains of all fallen bosses and Brain and Eye of Cthulhu for artificial intelligence, and mechanical bosses (Skeletron Prime, The Twins, The Destroyer, and [[Santa) for most of the body, and use all other bosses to fill in the gaps. Cthulhu Prime should have 3 eyes, which are Cthulhu's and the Twins, 2 brains, which are Cthulhu's and Ocram, has Skeletron Prime for the head, The Destroyer for tentacles (it will have tentacles instead of arms), Golem for the body, Santa-NK 1's wheels for feet, and can shoot lasers and can summon Mecha-Creepers, which form a force-field around Cthulhu Prime, and must be defeated to break the force-field, at which point CP (Cthulhu Prime) will try to run you over. Cthulhu will have 99,999 health, and Cthulhu Prime will have the health of all bosses (including Cthulhu) combined, and will be invincible until you use the most powerful weapon in the game (combination of all weapons including Terra Blade) to defeat either one of them, or all weapons will do 0 damage, and to get this legendary weapon, you must talk to the scientist right before you open the door to the final battle (he will not be rouge at that point), and he will give you the weapon, and you can't go in before you talk to him. Afterwards, the door will open and a blood curling roar/shriek sound will come out. At that point, the door will act like a black hole, and suck your whole world into it, and everything will be mixed up and chaotic. After you defeat him, a giant explosion of blood and fire will occur, and everything will be sent back to your world, as it should be. Afterwards, Extreme Mode will be triggered, which doubles the health of all monsters, and events such as Blood Moons and Goblin Invasions will be more likely to occur. There will be no bosses ex. Cthulhu Prime, which you must insert the Ultimate Weapon into the keyhole in the Door to R'lyeh, which is located even higher than Space in the heavens, and is guarded by Angels which will think you are evil at first. If you attack, they will automatically kill you, and you will drop everything you have. If you don't, they will know you are the Chosen One (kinda cliche, I know) and will let you through. The door will take you to R'lyeh, where you once again meet the scientist. He will tell you he has been trapped, and that if you give him the Ultimate Weapon, he will get you both out of there. if you say no, you will just be stuck in there until you say yes. When you do, he will laugh, and a colossal hole will open in the floor, and Cthulhu Prime will rise. He will insert the Ultimate Weapon into a hole in it's head, and it will start to move, as the scientist hops on for a ride on it. He reveals that he is the Devil, a servant of Cthulhu who vowed to restore him, and only let you defeat him so he could build Cthulhu Prime. After you kill the Mecha-Creepers, you won't be able to damage him, and the scientist will laugh. Then, the Angels will appear and grant you a weapon twice as strong as the Ultimate Weapon. One by one, you must chop apart the body parts. CP will then start to spark and will have smoke coming out of it, as it sets on fire, and the Angels will shield you, as there is the explosion to end all explosions. The fireball will reach your world, and the Angels' power will shield all that is good and holy in your world. Then, the credits will play, and after, a picture of Cthylla (Cthulhu's daughter in H.P. Lovecraft's stories, who is said to somehow give birth to Cthulhu if he dies) will be shown, foreshadowing an even more epic battle. But that's a story for another time. I looked at the Cthulhu sketch by TIY, and it is rising from the ocean, possibly relating to the fact that R'lyeh is said to be underwater. It also appears to be chained up for some reason. could someone have tied him up and sealed him is his underwater prison while he was asleep? I'm sure when Cthulhu wakes up it isn't gonna be very happy about this...
Do you like my ideas? Please tell me what you think in the comments!