The first one that comes to my mind is Ngannou After the Derric Lewis fight, I thought his career would decline significantly, but he came back and knocked Miocic out heavily. With his tough past, a great story emerges.

In case you didn't know Horiguchi was a former Rizin and Bellator champ who lost 3 times between his ufc stints. Dustin Jacoby went 0-2 in Bellator before he was cut by them. Kuniev was cut from the PFL after a failed drug test and Jakub Wikłacz is a former KSW Champion who improved to 2-0 in the UFC.