Whether or not the OP intended that kind of answer, these are the ones that I believe are most helpful to other players, so I post it whether that person is looking for something else or not.

If that is indeed the question, then it's the most pointless question one could ask. Luke is 115pts. Why on earth would it matter if a single character who costs 1/2 or less of his cost has taken him down in a one on one match up, particularly a melee character, which is what Luke is designed to kill? The game is played by squads. If this isn't a squad related question, then it isn't related to the game.

And further, his example of the time he did it was "a beefed up Lucien Dray". I'm pretty sure that was meant to include other components to squad building, not some made up one on one format of trying to beat 115 point piece with a 50pter.

If you read my examples, all of them started with Luke at full health. He can be beaten with melee pieces, the ones I gave were all direct examples of who I've used. Your best tactic isn't always to run right up to a full health Luke and start taking melee attacks. But you also don't do what so many people have said on the topic either, and never attack him with melee. It's all about timing, understanding the damage exchange and the odds. You play them right, and melee characters do just fine taking down Luke.

In the case of GMY for example - I was well aware that I could count on my Yoda to remove 60dmg from Luke (took out his support first including his Leia). However, instead of going right for it, I chose to keep Yoda alive, giving out his CE, presenting Luke with bait, and for force defense for an extra round. That made the difference between winning easily, and risking a 50/50 loss. Keeping Yoda alive, meant that I could defense a LS Defense on a 30dmg shot (defensed the reroll), kept 2 of my shooters at +3 attack, and that I could finish the game once I got Luke to 60.

Whether or not the OP intended that kind of answer, these are the ones that I believe are most helpful to other players, so I post it whether that person is looking for something else or not.