From left to right: Nouchi Masahiro, Shin "Yuri" Yurigaoka, Masaru "Iga-chan" Iga, Jiro "Tami" Tamiyama & Isao "Tommy" Fukutomi.
The Four Great Ones (Four Lords in the anime) are the leaders of Cromartie High's second year-students - or so they claim - who themselves are ruled by Iga. They are never asked to join in on fights, and ignored by the other students in the corridors. Opinions are divided among them whether this is a good thing or not - Iga sees it as a sign of respect from the others, but the others are convinced that they simply are outcasts.
Apart from Masahiro, who has styled himself similarly to The Great Muta (with different kanji on his cheeks for each story), all the members have make-up based on the Kiss members'.
They acknowledge how strange it is to call themselves "The Four Great Ones" when they actually are five members. Masahiro is often pointed out as the most likely to have to go, but the issue remains unsolved and often ignored in their stories.
These characters only show up in the last episode of the anime, and their one story is heavily shortened down to one punchline. One reason for this could be that their stories are more like those you find in the Slice of Life-genre, and that other stories would gain more from becoming animated.
Their only known voice actor is Kosuke Toriumi. (The credits of the English dub do not specify who the dubber is.)