#5 The Conquistadors II
The original Conquistadors were an enhancement talent tag team who mostly put over more famous duos like the Rockers.
Their identities were kept secret largely because no one much cared. Jose Luis Rivera would also wrestle singles matches as an enhancement talent sans the mask. Jose Estrada Sr. had some success in Puerto Rico and a brief reign as light heavyweight champion, but neither man generated much interest in the United States.
Fast forward to the Attitude Era, and Edge and Christian were in a bind. They had just lost a ladder match to the Hardys, the stipulation for which was they would not be granted any more title shots so long as the Hardys remained champion.
In order to circumvent this ruling, the duo donned the Conquistadors disguise. Fans, of course, caught on quickly, especially since the new Conquistadors seemed to use all of Edge and Christian's signature moves.
Then things got really complicated. The Conquistadors defeated the Hardys to win the tag team championships. A short time later, a fresh-from-the-shower Edge and Christian challenged two men in the Conquistador masks to a match for the titles. Unfortunately for Edge and Christian, the Hardys one-upped them and took over the Conquistador gimmick to re-capture the titles.
It was a hilarious, entertaining angle, and one of the rare times a heel team has donned masks to circumvent management.