#4 Ciampa wrestled for WWE and TNA at the same time
There was once a saying that wrestlers who had appeared on TNA TV would never make it to WWE because there was some kind of heat between the two companies, obviously, this has since changed since there are many stars like Samoa Joe, AJ Styles, Bobby Roode, and EC3 are all carving out quite the career for themselves in WWE.
It appears that there are many more names on that list since Tommaso Ciampa also wrestled for TNA on numerous occasions. Ciampa returned to WWE back in 2015 and signed a deal that allowed him to still appear for Independent promotions alongside his appearances for the WWE, which included working for TNA.
Ciampa wrestled twice for the company in 2016 whilst also working for WWE, but was then signed to a much more demanding contract and went on to become one of NXT's biggest stars.