The Crystal Tower event was interesting, but definitely easier than magicite stuff. Got the full CM clear first attempt with the following teams:
Squall -- Maria, Emperor, Raines, Papalymo, Yuna
Scylla -- Luneth, Celes, Refia, Onion, Arc
Adamantoise -- Ashe, Desch, Alphinaud, Edward, Iris
Adel -- Squall, Shadow, Vaan, Ramza, Yshtola
Video:
Crystal Tower CM
Squall was just a dps race, so I went with 4.5 dps and burned him fast. Scylla's only gimmick is the petrify, so I used a Unicorn magicite for astra. Adamantoise's gimmick is aoe confuse, so I wore confuse resist on everyone, and Adel's only gimmick is draining Rinoa, but he died so fast that I could ignore Rinoa entirely.
I thought there was supposed to be a 5th final boss for these events, but I guess not? Not sure if this one was special, or all future crystal tower events are only four fights. I preferred the 4 mini-boss then a final boss like the anniversary version.