Neoverse

I thought I would share what I did to earn this achievement.
I used Helena to do this mainly using the White Lion guardian.

I used these gears. Oni Mask, Dark Energy, and Jack O'Lantern for the 30 skill points.
I used this method to get all the way through Transcended lv 15.

Use either the Offensive or Defensive type starting decks to get the Guardian Selection card. I am not a fan of the "Your Name Is" card from the Hybrid deck for selecting the guardian. Unless of course the Daily deck is quite good.

There are a few skills I highly suggest going for first to help out. The skills Establish Command and Beastify really help since they will give you armor for the things you'll end up doing anyways with Helena. Also, there are other skills that give armor and the skills that give you extra mana at the beginning of turn/battle are quite worth going for if they are there. It is randomized what shows up.

Cards to look for that will really help from the battle rewards are anything that will activate your guardians ability (especially the ones that activate your guardian multiple times like Beastify and Multple Orders) or you gain armor when the guardian activates like the Dragon Scale.
Constants like Master of the Guardians will help since it gives you a free guardian activation at the beginning of your turn. Or Bless of Earth where you get more Mana at the beginning of the turn. Or even like Getting Used To Loneliness to gain armor whenever you use mana.

I was able to activate the guardians ability 4 or more times plus gain 20 to 30 armor per round . This helps mow through most battles quickly and reliably. The only battles that give trouble are those with a monster that can dismiss all of your armor. Still get as much armor each turn you can because the monsters that attack usually attack first before it gets to the one that cancels your armor.

I didn't go for the loop deck because trying to get either the cards needed are getting rid of all of the extra cards took too much time/luck.