Sins Equal To The Entire Ummah

Imam Ali(as) said:

Muawiyah and his son, after Usmaan, will be rulers and after them from Hakam ibn Abil Aas, seven people will become rulers who will be one by one until 12 imams who will misguide are completed. 

And these are those very people whom the Holy Prophet(saww) saw on his pulpit reversing (from religion) the Ummah. 

Ten from them will be from Bani Umayyah and two (Abu Bakr & Umar) who laid foundation for them and these two - the sins will be equal to the sins of the enitre Ummah

Source: Kitab Sulaym bin Qays al-Hilaali Hadees 11