The Krogan are a highly aggressive race whose history is filled with conflict both within the race and against other races. Their discovery of nuclear weaponry nearly wiped them out. They were instrumental in the victory of the Rachni Wars, but rebelled shortly afterwards and were infected with a genophage that left many of their females infertile and dramatically reduced their population numbers. The Krogan homeworld is Tuchanka. Notable Krogan include Urdnot Wrex, Urdnot "Eve" Bakara and Urdnot Grunt.