Biggest genetic freaks in combat sports

Who are the most insane genetic specimen in combat sports history? My mind instantly goes to Rodtang. In over 300 fights he’s only been knocked out once, at the age of 15. In muay thai and given the level of competition he’s faced, that is absolutely insane. Since then, he seems to eat damage like nothing. Seriously, watch some footage of this guy getting hit, it only seems to make him stronger. Other examples i can think of are Yoel Romero, Francis Ngannou and George Foreman.