Brachyura

Brachyura is the scientific name for "true crab". Three different types of Brachyura have appeared in Castlevania. Each kind uses bubbles as one of their weapons. The first was a robot crab that crawls in between indentations of metallic walls in Boku Dracula-Kun and Kid Dracula. The second is a Skull Crab, a Crawling Skull consisting of a skull with legs made of bones. It crawls around the ground and emits foamy bubbles as attacks. The third is the giant crab boss in Castlevania: Order of Ecclesia that scales between the walls of the Lighthouse.

Castlevania: Order of Ecclesia
Brachyura (ブラキュウラ) appears in the Lighthouse as Order of Ecclesia's 3rd boss. This fight isn't so much about killing him as it is about getting to the top of the Lighthouse so you can access the elevator to kill him. The Macir & Torpor glyphs work very well in this boss fight. The objective of each part of the fight is to keep attacking him until he turns red. While his color is green, he will use three different attacks. If you are on the left side of his claw, he will attempt to punch you. If you are on the right side of the claw, he will insert the claw into the smaller pincir, build up energy, and let go as the back of the claw slams into the wall. When he turns red, he will then use his giant claw to punch out the ceiling of each section of the Lighthouse. Both colors will also fire acidic bubbles at you, although they are faster when his color is red. As you get to the top of the lighthouse, you will find an elevator that you can ride down to the bottom to destroy him.

When you unlock Boss Rush Mode 1, the Lapiste Glyph will make it faster to make him turn red and punch through the ceiling. The Volaticus Glyph helps by allowing you to get to the top faster. However, you end up wasting time by having to wait for him. if you want his medal on normal mode use arma machina to avoid damage.

Trivia

 * Brachyura is meant to be a spoof of the "Giant Enemy Crab" meme, as is made evident by the medal calling it a "giant enemy crab" and its description, which says it hails "from the depths of Transylvanian history".
 * Brachyura is one of the few enemies where Shanoa actually speaks to. When she is about do deliver the coup de grace to it by the elevator, she says "Go to hell".
 * Likewise, Albus delivers a reference to Konami's Metal Gear Solid by saying "Showtime" in a tone similar to Solid Snake.
 * The existance of the game Castlevania: Order of Ecclesia was first leaked when someone posted an image of Brachyura dubbing it as "Blackula".