So, I was doing a run through on master mode for the first time, and lunatic cultist was just mopping the floor with me. Especially when I would accidentally hit a clone, and the dragon just annihilated me. So, I noticed his pattern was fireballs, ice ball, lightning, fireball, ice ball, clones. So this made it easier to predict WHEN the clones were happening, but not how to get around smacking one, or being able to tell which was which fast enough. I then noticed the correct clone had a gold stripe on the top of the hood! So now I know when it happened, and how to tell which was which, but as a melee using Terra blade, it was still hard just hitting the right one. So I started using the keyblade ONLY on the clones. This is your when, your which, and your how on how to fight lunatic cultist.