The Xavier Protocols are a set of doomsday plans created by Professor X. The protocols detail the best way to kill many powerful mutant characters, including the X-Men and Xavier himself, should they become too large of a danger. The Xavier Protocols are first mentioned during the "Onslaught" crossover and first seen in "Excalibur" #100 in Moira MacTaggert's lab. Charles Xavier compiled a list of the Earth's most powerful mutants and plans on how to defeat them if they become a threat to the world. They are first used after Onslaught grows too powerful. Only parts of the actual protocols are ever shown. In the "" crossover Bastion obtains an encrypted copy of the protocols, intending to use them against the X-Men. However, Cable infiltrates the X-Mansion and secures all encrypted files before Bastion has a chance to decrypt them. Due to the tampering of Bastion and his Sentinels, the X-Mansion computer system Cerebro gains autonomy and seeks to destroy the X-Men by employing its knowledge of the Xavier Protocols. In a virtual environment created by Professor X, Cerebro executes the Xavier Protocols against the X-Men.