Sentinel: First invented by Bolivar Trask, the robotic Sentinels were tasked with containing and destroying mutants. Notoriously difficult to effectively program and control, the use of Sentinels almost always ends in tragedy.

Rachel Summers: The child of Jean Grey and Scott Summers from the Days of Future Past reality, Rachel Summers was forced to serve as a "Hound" by her slaver captor Ahab. Later free of the brainwashing, she would join the Excalibur team.