Here's an early pair, with Harvey Dent's return...and first appearance?
Two-Face Strikes Again!
Here, Harvey was trying to put his criminal past behind him, but a chance robbery, with Dent going in to stop the criminals exposed him to a small explosion, undoing the surgery, condemning him to a life as Two-Face (which he permanently decided with a flip of his coin, which landed scarred side up).
After gathering a gang, Two-Face went after others with two faces (clowns, actors) keep ahead of Batman and Robin, until Batman offered up his own identity as Bruce Wayne (receiving an award for aiding a native American charity) to lure Two-Face out, getting Batman and Robin a chance to capture him, but getting caught in Two-Face's coin trap....which they defeated, then captured the criminal.
Half An Evil
This time around, it was only Batman available to face Two-Face, who used a pair of clowns to steal a parade balloon and a book from a nautical museum. After recounting Two-Face's origin to Alfred (how Harvey was half-scarred in court by a criminal throwing acid, cured and then redamaged in an explosion), Batman went after Two-Face and his real target, a boat at a marina, which Two-Face sinks! Batman figured out Two-Face's real plan...to use the parade float to raise the boat later, to plunder it at his leisure. But, by showing up, Batman forces Two-Face to speed his timetable, tying Batman to the boat and deflating the giant balloon.
Batman convinces Harvey to flip his coin to decide if he should save Batman, and the coin comes up good, so Two-Face heads back to the sinking boat (which Batman has already escaped, capturing Two-Face on his return).
These two stories above, as well as his original three, along with others, are reprinted in Two-Face: A Celebration of 75 Years, which came out in 2017.