Hi all,
I started playing around two weeks ago (My daily login is still at 3rd week 2nd day) and I managed to clear all 21 trials. I got lucky with 400 diamond RNG pull seraphina, but I managed to clear 15/21 BEFORE getting seraphina. I'm pure F2P by the way.
1st) I cleared the legendary stage using seraphina ally with attack higher than 3500 fairly easily with green consumables before getting my own. (keep refreshing ally list till you get one). My current team:
5* Vincent Gladiator
5* Kane GrandRanger
5* Cybella GrandRanger
5* Freya Dragoon
1* Fodder (to swap)
I admit I got lucky with the freya pull, but if I remove freya from the lineup I'm still able to clear at least the first star of each legendary stage.
2nd) After getting my own seraphina, i'm actually farming the middle stage and MOST of the time I finish in less than 15 rounds (Without a single consumable). I removed Vincent from the lineup and sub with my own seraphina.
My Strategy: For the first round, I just end turn (Note that I placed my freya one square back, to ensure the mobs kill the fodder & hit seraphina (Freya might die if i place her in the front.) I know people will say it's a waste of one round, but it is to ensure my seraphina is out before the chest round.
Second round, chest round, I just focus my dps on the front two chests. After that, I move forward and continue killing (I can pretty much auto) UNTIL the chests get their skill, i'll use Freya to jump in the middle and stun all 3 chests. After that, my two seraphina will kill the middle chests and move forward. I will then use Kane/Cybella skill to delay one more turn and finish off the chests.
(People will mention again, I wasted TWO more turns delaying here)
The main reason I delayed the turns is to make sure my full lineup goes to the last round, and last round is pretty much auto. If I get lucky with the triggers, I'll finish at around 12-13, if not 15 and sometimes 16.
I admit I got lucky with the pulls, (If i didn't get Seraphina, at least i can clear 15 rounds) but I manage to achieve 15 rounds and consistent farm on Legendary even without my Freya.
Screenshots :
http://imgur.com/a/qnN6B (10 turns left when reaching boss stage, cleared at 14. Ally Seraphina had a bad aura direction, but still did okay)
This post is not to brag, just hope my strategy works for anyone who is struggling, there are people who post in facebook saying they can't clear legendary with 3 seraphinas, I don't understand why.